Why does the `register` tag get converted to `formality`?

Question

I wanted to indicate that the phrase got a steal is in a very informal register:

I just got a steal on a lawn mower down at the hardware store. They're going out of business.

I edited a question to add the register tag and it was converted to formality.

Answer 1

The proposal to make register a synonym for the tag that is now named formality was created by StoneyB back in 2016.

All active tag synonyms