If you read GP's comment closely, it's worded such that it acknowledges this point (though I admit it could be made even more clear).
Now consider the massive increase in dominance of these strains, not where or how they originated. That is what's relevant to the sources I've provided.
Hopefully with that cleared up, through your "temporal logic" and "direct inductive reasoning" you'll see that the timeline on which these variants came to dominate matches very closely with the mass vaccination efforts.
Sorry, I mixed your comment with somebody else's which used the word "emerged" and argued delta and lambda appeared because of the unvaccinated.
On the rest, not arguing on the mechanics and dynamics of the epidemic.
The only meaningful effort made to systematically track the vaccination effort effects since day one is Israel's 580K control group matched cohort. The UK is not quite at this level of details, let's say. Those two countries are not enough.
Most of the rest which I seen is "let's throw a model at the wall and see what sticks", followed "the study is under-powered but let's publish anyway", concluding with "have clueless random msm journalists and anti-covid-vaxx sleuths misquote the results".
On that account, I don't really trust anybody's observations either way quite yet. We'll have to see the post-mortem in a couple year's time.
Selective pressure _can_ certainly apply, and as it has in the past, and you pointed it out correctly.
However, my point is here it _can't_ have. The timeline simply doesn't work (see https://news.ycombinator.com/item?id=28078077 for all variants).
It's literally entropy, or karma, or god, whatever you may believe : everybody was unvaxxed in India at the time. This particular Delta variant, it can't anybody's action or lack thereof in regards to vaccines.
As for the other variants, well, you might be very correct. I don't know, haven't looked into it at all.
And to be pedantic, please let me point out citing models of a natural mechanisms and suspicions by respected researchers who are probably right is not a "critical fact", it's a "well reasoned argument".
Similarly, I won't use models and past experiences projected on current unknowns when temporal logic and direct inductive reasoning gives you an unambiguous answer.