It would be handy to have a current gen Formula car for custom grids, though.
Luckily the SF19/23 does that quite well but the 22/26 styled cars would be very cool to have. Or even use aero parts on, say, a 2000s F1 style car to turn it into a 26 esque-car. You wouldn't have the hybrid system though.
I actually don't mind the 22 regs. I'd prefer a V8/V10 for the theatre but I think the 22 era cars look good and sound alright. 26 regs look good in concepts, not sure how they'll sound.
From what I read (a comment talking about a reported conversation, so not a primary source), they'll be at full revs a lot so that might help - but either way I can imagine for sure people would prefer a 2000s era F1 car.
If the 26 concepts turn out as they seem then a 2007/2008 F1 car would be a good analogue visually.
If they can add a hybrid system it'd honestly not be far off. But even if it's just visuals I think the 07/08 cars might be a good way to cover both eras in a sense.