Maintenance
A WordPress website is alive: the core, the theme and the plugins all get updates, and you have to check that one update doesn't break another. That time is real, it comes round every month, and it appears on no quotation.
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WordPress runs a huge part of the web, and for plenty of projects it is the right choice. So the question isn't which one is more powerful, it's how much time you want to spend maintaining your website.
A WordPress website is alive: the core, the theme and the plugins all get updates, and you have to check that one update doesn't break another. That time is real, it comes round every month, and it appears on no quotation.
Their sheer number is a strength, and it is also the first source of trouble: an abandoned plugin becomes an open door or a broken page.
The software produces pages, and those pages don't change. They need no security patches and no monitoring: they are served exactly as they are.
A busy blog, particular business needs, a directory, a membership scheme: when each thing calls for a plugin, that is where it belongs.