I've heard this a few times lately, but this past weekend I built a website for a friend's birthday, and it took me several hours and many queries to get through my regular paid plan. I just use default settings (Sonnet 4.6, medium effort, thinking on).
I'm guessing Opus eats up usage much, much faster. I don't know what's going on, since a lot of people are hitting limits and I don't seem to be.