Why hasn't there been a GPT/LLM spam/scam wave?

Probably because scammers are still using the same old scamming mechanisms, just with LLM support. What technology the scammers are using behind the scenes is invisible to the recipient.

I think this may be happening with scam/spam email. I've definitely been getting more than usual in my inbox.

And scammers are using AI generated voices: https://www.npr.org/2023/03/22/1165448073/voice-clones-ai-sc...

There's definitely been more spam, especially in small forums.

A favorite tactic is to make a couple dubiously-related posts (to look like a typical newbie) and then go back days later to edit in SEO-spam links.