That’s a really slow review process. It also prevents reviewers from seeing the bigger picture of how step 1 manifests in step 2. In practice what I’ve seen you end up with both reviews simultaneously referencing each other in the description and once approved you merge 1 and update the pointer in 2 to point to the new merged commit if it changed.

That’s a lot of annoying and sometimes error prone manual bookkeeping that has nothing to do with the engineering work itself