I understand that ignoring someone’s post and happily going on to quibble on a perfectly reasonable sentence is hardly good manners, but I will look over it and keep taking this seriously and answer your question, since English is both our second language and there is a chance that this is still a misunderstanding and not quibbling:
The sentence you quoted has two parts hence the comma and the “but” separating them. In many cases the word “but” is a synonymous to “however” which means that "despite what sentence A is saying, sentence B is heading off to say something else.
For an easier explanation here:
Therefore
Sentence A means:
I have yet to understand what is your exact problem/issue with what I have said so far, because you haven’t made a clear statement of what your actual opinion (or disagreement) even is, other than a general feeling of dissent and just tossing a link for a paper that was full of holes which you failed to notice most probably because you didn’t read it nor considered it much (hence the post above, which you mostly ignored).
and Sentence B means that despite “Sentence A” I will keep taking this seriously and I will go on to discuss further that very particular point you made (about me supposedly not putting enough scrutiny in my posts) and inform you that the whole issue of the potential EV used car market, was actually a point in favour of what I was saying all this time (and I didn’t go into it earlier for brevity’s sake, as you will see in the spoilers below. This is a very complicated matter after all).
Now, hopefully, this misunderstanding has been cleared. 
The essense of the matter remains above for everyone that would like to consider it. My points were as clear and conscice as I can possibly make them for a forum and if you’d like to argue with them I’d be happy to hear what your issue is with those points.
If not, that’s also good, since I had a nice time looking into all of those things. I was not aware of that article and that paper it was based on it and it really drove in the point that I’ve been making in fora for years that we should never just trust papers and headlines blindly and we should really look into the research we are being peddled and thinking critically about it, before putting it in our minds as a “potential fact”. Now, I know that I fail to do that a lot (who has the time to read everything, after all), but it is a good thing to be aware of the issue.
Correct. I agree with that and it is part of my point.
I mentioned this as an indicator that there are countries where it is/was the norm to change cars every 4-5 years. Sell the old one down the line (be it within the country or outside of it) and buy a new one.
That is what has been happening with the gasoline/diesel cars and we know that and we have data for that (which you have provided and I never argued against it) because that technology is 100+ years old and therefore the used car market for those cars has a lot of historical data for those cars, but we do not really know if the EVs that are getting replaced at the 4-5 year mark, are in fact getting re-bought like their gasoline/diesel equivalents do.
So, I would even go on to say that:
…the estimated gasoline/diesel car’s lifespans could even be longer than that. Even 25 years or 30 or 35 because in many cases that car is not scrapped, but sold in another country where it is out of the French system, but it exists in some other country and they can be found/driven there for many more years (like Top Gear found those cars in Botswana).
However, those are all data for gasoline/diesel cars.
The EV “used car” market hasn’t even been around for 20 years (the reported lifespan of an “old-tech” car) and there are no similar data for EVs for the span for two decades. For example, from your links (if I understand them correctly, my French is laughably bad 
)
This here says that the thermic cars are 89% of the market and if you add to them the non-rechargable hybrids (which are essentially still thermic cars, which a battery that cannot move the car on its own), that goes up to 94%.
You cannot look at the data of that market and extrapolate those numbers for the EVs or the hydrogen cars, because they are very different technologies, with very different used-car markets.
And then there is this:
Which, if I am reading this correctly, means that in order for a car - on average - to reach the range of 120000-130000km on its odometer (where that 122792 kilometers point lies), it will need 10 years on average (though EVs would probably take longer for average, since they are mostly city cars and are driven in shorter trips daily, but let’s not get into it, again, for brevity’s sake). Combined with the above, it means that a lot of those cars will cross that threshhold with their second owner and that’s fine for gasoline/diesel cars because we know the used market for those cars is very robust.
But for the EVs? We do not know, because their used car markets hasn’t really been around for 10-20 years. At the moment, because it is an emergent technology, most EVs do not have a strong “used car” resale (I won’t bore you by re-writing the potential issues, I mentioned the four main ones in my previous post) and a lot of them are, unfortunately, scrapped or “recycled” (it should be noted that gasoline/diesel cars are more likely to be repaired after small accidents, while EV cars are more likely to be declared “totalled” not because the car is destroyed, but because the batteries are too expensive to replace and so they are sent for scrapping. Again, not very enviromental and, again, let’s not get into that for brevity’s sake)
If you look my previous points, I never claimed that EVs cars are bad or that gasoline/diesel cars are better. Each has its usecase and I’d buy an EV myself, if I was within one of its usecases.
On whether the EV cars are better for the environment that the gasoline/diesel cars, we do not know yet, because it is a long-term issue and the EV market has not been around long enough for us to have long-term data. @trohde raised a very good issue and that’s, as far as I can tell, the most honest answer. Car companies and car sellers love to advertise “buy this for the good of the environment”, but so far noone knows if it is true or not, long-term. Not me, not the car companies, not the MIT, not anyone. Because not enough time has passed to make a judgement on such a thing.
Heck, even far more simplier ideas are still under review:
So, even simple things like straws are hard to gauge long-term, so saying that we need to wait a few years to have a verdict on complex products like EV cars, is hardly controvertial or illogical.
) about "Quantifying efficiency technology improvements in U.S. cars from 1975–2009"… what on earth has that got to do with 2019 cars? Pray tell us. Should it at least have come from a report on efficiency improvements of 1975-2019 cars?
Come on.
)