Python 2 -> 3 change really was painful for Python community, but PHP does these almost fundamental breaking changes so often, that maybe people just get used to it? I haven't really followed Python past version 2, but I think they are less likely to ever do such amount of breaking changes.
There must be a lot of unmaintained PHP codebases that will break if PHP is updated by hosting provider etc. Someone must be pulling a lot of hairs because of this.
Edit: Those dogpiling there, I rest my case with josefresco's comment:
https://news.ycombinator.com/item?id=33907628
It's painful. Dropping dynamic properties? That will be a lot of fun. WordPress is probably biggest segment for PHP usage.
I have a private (non-internet) web-app that's still on PHP6.5; I like the new PHP features, but upgrading private code to conform to PHP 7 and 8 looks a lot like make-work. I wish it shipped with good upgrade tools.
[Edit] @darkwater (below) is correct; I meant PHP 5.6. PHP6 was some kind of abortion - I can't remember the story.
IIRC, the initial development was in the mid 2000s but it was abandoned several years later because they couldn't get Unicode support working correctly. By the time it was abandoned there was already a lot of material referencing it like books and conference talks. So when the PHP team decided to do a new major version most of the planned PHP 6 features were already added to 5.3 and 5.4 so they thought it best to just skip 6 to avoid confusion.