It’s possible to self-host wordpress (meaning you do not have to use wordpress.org hosting). It’s built with PHP and mySQL. It’s very well documented and has a HUGE community of users. It’s one of the most widely-used site builders on the internet (about 43% of all websites) so it’s easy to find solutions to any problem.

I don’t know about Hubzilla but I suspect that it’s much more difficult to find answers to questions because it has a smaller market share.