I just did that.
Sitting here typing this out on a 2017 iMac 5K 27" that's now dog slow and stopped getting new MacOS versions last year.
I write Apps for a living. My running copy of Xcode is now a few versions away from the current as it stopped getting updates earlier this year.
If It hadn't been an iMac I'd have ditched it for a M Mini already.
Sitting behind me right now is a Studio Display I bought awaiting a Mac Mini M4 that I ordered which, according to DHL tracking, is with my postman now.
Yes, there's cheaper ways of doing this but I'm not buying it, my business is and it's doing well enough.
I did think of gutting my iMac for the 5K screen and I might still do that. My teenage, PS5 owning, son has been begging me for it.
I just wanted a complete refresh after seven years.
Honestly if Apple had offered a M4 27" iMac I'd still have taken this route.
Just feels like such a waste of a really good 27" 5K screen all because the Intel i7 is now dated.
The screens aren't changing much. The Studio is much the same as the screen I have in my iMac.
The processors on the other hand...