TBH, I don't think PHP is going in that direction.
This was one of my requests to that new search engine posted here a few days ago.. Filter on minimum version of technology. Should actually just be a field in stackexchange.. packages/languages references + version. And a marker to set if the information is obsolete.
You can't get rid of old stuff in the name of BC, but you often simply don't have to use that old stuff. For example, people hate on JavaScript (and PHP too I believe) for the semantics of their "==" operator, but it's a moot point since these languages have had "===" since many years.
Every beginner knows that because all recent books literally say "don't use ==, use ===", modern IDEs will point it out for you and 1st code review feedback will point it out.
What usage of this moot point showcases for me is mostly author's blind bashing without real knowledge.
Many languages are unityped and carry the same problems, yet they are hyped rather than bashed (e.g. Python, Ruby).
> If you know why you shouldn't use `==`, you know enough so that even if you don't go for `===`, using `==` safely is the least of your problems.
You have some weird false dichotomy going on. I'm personally in the state "I remember why == is bad (type coercion ...)" but I don't remember all the details to be able to use == correctly. I bet many people are in a similar situation.
You can, it just takes ages and dedication and will cause a lot of friction. See: Python's changes between 2.x and 3.x, .NET's breaking changes between 1.x and 2.x+