After more testing:

I get the what, but I don't get the why ? why would we want to do that, you are the first one proposing such change in a decade at least

https://github.com/freebsd/pkg/commit/4aece431e88137f0ebb6ff266cdf8bbd24764699 for the record ;)

I think the requirement for "recent" amd64 machines is ok, Nehalem is from 17 years ago also people with older CPUs can still install their own linux chroot if needed. (still an entry in UPDATING and probably also pkg-message would be nice).

with @ziaee changes incorporated

I think you will need to make the transition period longer than current as it is already in 14.x or this should be merged in 14.3 as well. It might be interesting to issue a warning when ':' is encountered so users know they should upgrade their setup (could be in a separate commit)

the -o is on purpose to preserve interractive prompt, if you want to prevent that, then you need to make this conditionnal to BATCH: if BATCH then xargs pkg install -yA if not xargs -o pkg install -A

yes, I will do it

rename the variable