This is good and all, and many of the comments here explore the nuances. Something all of it seems to miss is that one persons "senior" engineer is not another

This is good and all, and many of the comments here explore the nuances. Something all of it seems to miss is that one persons "senior" engineer is not another persons "senior" engineer. This designation is meaningless and it usually is a failure of a company to properly assess their needs when creating a role. Some approach it by using a wishlist of framework and language knowledge (that quickly turns into a checklist). Others approach is by years of experience doing x,y,z. Fact is, a "senior" engineer is code for "person I want to hire who is right for the job and who needs little guidance". Many people fit that bill.