This is good. Boeings problems can be slowed down if they stop producing that airplane. They need to simplify and regroup. United just gave them another reason to do so. Let’s hope other airlines follow.
Finally, killing off the 10 will likely force Boeing to actually build a new plane instead of iterating on a half century old design.
Personally I hate the 737. It needs to be put out to pasture and replaced with an aircraft design that represents modern ideas.
AA just ordered a ~100 of them. They are still making the Max10. And the problem that has caused certification issues for Max10 still needs to be fixed for Max9. Just not a big enough issue to ground existing planes.