But note that the most it can possibly do is support the core of SMF - not any mods, especially not bbcode mods, all of which need a rewrite.
(Well, I say that. It's theoretically possible to write a package manager package that does it, but it would be a one way only patch, with no ability to revert if it goes wrong, and if it goes wrong it takes your entire forum down. And none of the mods would be able to uninstall after because the code that they added would be entirely removed. And if you upload a new batch of files, then add mods, the mods break again. Or if the mods use hooks, it's all redundant anyway because they still don't work properly on PHP 7.2 even if the rest of the core could be patched. So, yeah, net result is that only the core can be patched.)