Waterfall was good in a time where requirements were more static. It's not great when you don't know the requirements fully or they may change during the project.

I'm not a fan of agile either though. I'm not a team player and agile is way too heavy on the framework side for me. But some parts of it are ok like close collaboration with the (internal) client.

Luckily I work for a company that thinks logging our hours in Jira means we're agile so I don't really have a lot to do with it.