There are still a lot of people who need Intel, primarily people doing cloud development and in particular those who aren’t using an interpreted language.

I don’t how big this group is as a percentage of Apple customers, but in an absolute sense it’s significant — several $B worth anyway.

Also there are people who won’t buy M1 because they are (probably correctly, though I haven’t had any problems) hearing that not everything works right yet. If my mother needed to replace her MacBook Air today I’d get her an Intel one. I expect her next machine with be Mx though.

I suspect Apple will continue selling Intel-based machines into 2022, and perhaps longer. I doubt they will update them though.

They said the transition would be completed within two years. I imagine they have a pretty good idea how many people are using Bootcamp or Windows VM's and have already decided it isn't significant enough to stop them transitioning.

I assumed they meant every Mac in the product line would have an ARM version. I presume a few of the Intel-based SKUs will remain until demand ebbs, but probably not every one (e.g. perhaps only the 16” MBP and the Pro)

I suspect they won't want Intel hanging around any longer than necessary because it will delay the point where they can stop supporting both architectures in future versions of macOS.