I think those people will end up buying the cheaper, but much higher margin PlayStation 5 Slim a year later.

I’ve also heard some speculation that the curvy shape is specifically designed to keep people from impeding cooling by stacking things on top of it.

The time difference between regular and slim consoles being released has been pretty much spot on 3 years for all consoles, on all generations going back 20 years. If Sony releases a slim PS5 "a year later" that would be unprecedented.

I very much doubt that those are the people who are going to be buying PS5s this holiday season.

They are, if they have a job. Not being sarcastic, it's just that 500 euros/ dollars is an ok amount for a piece of entertainment that will last a few years, so they will buy it now even if they are not playing all day long.

I think not because they're going to be hard to find and casual players aren't going to F5 the page all day trying to get one.