For where Sonski is or isn't on the ballot, and where a write-in is allowed, see here (scroll down):
https://www.petersonski.com/Right now, he's on the ballot in Alaska, Alabama, Arkansas, Florida, Hawaii, and Ohio. Of those, only Hawaii would be a blue non-swing state. But lots of other write-in states across the spectrum from deep red to deep blue.
As for whether it's an effective way to send a message to the GOP, they don't care what we think since their interests are in a different direction. The GOP is pretty much telling us to take it or leave it.
The question possibly worth considering (if only for the sake of discussion) is whether voting ASP could be a moral option in 2024 for those who simply feel committed to the civil act of voting.