At least PHP doesn't have the whole Python 2 vs. Python 3 fiasco. And a gazillion different ways to package and install dependencies. Don't get me wrong, I love Python but every language has its warts.
Manageable is subjective. There's no evidence that it's "just right" or even "timely". Major API cleanup would be appropriate for php 8 but there's still too many people clinging to the idea that PHP would be damaged because someone can't look up how to solve PHP problems with specific versions (ie are stuck in the late 90s).
There's so much that could be done in one fell swoop, the steering council of neckbeards (PHP neckbeards are as bad as it sounds) are responsible for the stunted development of the language. To suggest they are the progressive face of PHP is, at best, revisionist.
There's plenty of features in the docs that say at the top "deprecated in x, removed in y, see also alternative z", so I'm unsure of what problem you're referring to.