I'm inclined to agree. There's a wordpress plugin for almost any generic use case one can think of. Social media site? Ultimate member and a bunch of others have that covered. Need it more customized? Jump in the source and fiddle until it does what you want.

I just did that yesterday. I needed to control access to certain pages to only include users that have paid for credits using stripe (provided by WP simple pay). I modified the Wordpress Access Control plug in and in about an hour I had a solution for a very specific use case.