Lines are blurring there nowadays tbh

Difference between 12 personnel and 11 personnel is who is lining up in the slot. Line up a passing game TE there (F) and it's 12. Line up a WR there (Y) and it's 11. So it's a question of the matchups, i.e. who gives you the best looks vs a specific defense.

2020 brought higher percentages of 12 sets due to lack of speed at wideout. 2021 brought big speed at wideout so it is likely we see a ton more 11 once again.

It's also inevitable due to the lack of experience at TE too. You have Higs and upside types (Harris, Hopkins, Skowronek) then a depth type who struggled in the run game last year (Mundt). I expect the final roster will have Higs with Mundt as his backup, and then the best performers overall between the young upside F type options will probably have two slots.

If you line up Higs and Mundt you're giving up pass game threat for incremental (IMO) run game improvement. Or Higs and Harris/Hopkins/Skowronek you're giving up speed for size. So for 12 sets to factor in they will need one of those three guys to make a move and show something in the passing game. IF that happens then you can say that 12 set offers size so you now have a 12 set that can help you in the redzone and certain other situations.

However that F part of the roster shapes out I think the teams factors in really big. Because whoever is a stud on teams will get to be up for gameday. Which means you're there and ready for some snaps as opposed to what happened with Hopkins last year.

It's also why Hopkins is fighting for his job this year IMO. He may be a one and done guy.