my thoughts and prayers to the stubborn php 4-6 developers who refused to upgrade since 7 and now they have breaking changes with the new 9.2
Probably easier to back port the patch to 4-6 code than upgrade to 9.2.
Once it's out it's likely to be an easy "disable this damnable feature nobody needs" as usual.
I fought hard about four years ago at a previous company to upgrade us from PHP 5 to 8 because I think 5 was going EOL or something like that (could be wrong about that now). Based on my experience in software, I have to imagine the vast majority of normal developers do not give a damn about security in being in security patch lifecycles on software.