Starting from 1997, over the years I completely replaced PHP with Python. Apart from the language itself, which I like a lot for many reasons, some benefits that come to my mind:

    - Better libraries and frameworks overall
    - Better programmers overall, so more competent colleagues
    - Relevant in many fields outside web development
    - Allows to learn and use various paradigms, like async/multithread/multiproc...

I do keep track of PHP improvements. In fact, I keep a small personal toy framework as a way to test its new features. Some of these were very much welcomed, like safe mode + runtime typing. But some of these were just catch-ups and none of these are compelling enough so that I would want to start a new project in PHP.

Other ecosystem I'm interested in is Go, for other reasons.