Modern PHP is much better than most people expect. It has very little to do with the PHP4 we all grew up to dislike for its quirks and inconsistencies.
That said, I wish more software was done in PHP. And for me it makes a lot of sense regarding the Fediverse. A PHP platform I can put on my existing shared hosting and connect some (sub)domain to it and call it a day. Most smaller/meduim businesses probably have that hosting constellation already around, idling around most of the time. The entry barrier is just so much slower than spinning up a VPS or renting cloud space somewhere just to test a small instance of something. Sure it scales not as good as your average cloudplatform but for most usecases that is not the biggest concern.
Different product but I love Matomo as a Google Analytics because I can just copy the files to a clients shared hosting, connect a subdomain to it and if it uses Sqlite (also better than it's fame!), I am done already and don't need to create a database even.
Kudos for saying that even as a massive PHP hater :)
IMO there is a reason why Wordpress is so popular (Disclaimer: massive Wordpress hater here!). Because of ease of install, more people can upload some folder in an (Web)FTP client than spinning up a Docker Container somewhere to host the latest JS Framework of the day just to host their little page or to show their content.
There is simply no need for bundlers, preprocessors and often not even [a lot of] package management (I'm aware of PHP composer though)
And exactly that ease of install is what could IMO make the Fediverse more democratic than having to run a container at some VPS that only a comparetively few people are able to do.