If you’re using “trunk-based development” (everything is a PR branch or in main), this works great.
If you’re using GitFlow, it can make PRs between the major prod/dev/staging branches super messy. It would be nice if GitHub would let you define which merge strategies are allowed per-branch, but that’s not a thing (AFAIK). So you’re probably better off not squashing in this situation.
If you’re using “trunk-based development” (everything is a PR branch or in main), this works great.
If you’re using GitFlow, it can make PRs between the major prod/dev/staging branches super messy. It would be nice if GitHub would let you define which merge strategies are allowed per-branch, but that’s not a thing (AFAIK). So you’re probably better off not squashing in this situation.