With Opus 4.6 on the $20 plan the limits were bad, but at least you could do a short session.
I find that with Opus 4.7 I can do two messages. Once I had a short session with 4-5 messages and it consumed $10 in extra usage.
This relegated Claude to a backup option in addition to Codex, which has the better desktop app anyway, and much better usage limits.
I’m considering to even cancel Claude entirely.