Many language allow an alias name. Which means you change the name and then alias the old name to the new line - 2 line PR. Then a bunch of one line PRs to change easy use of the old name. Finally a PR to remove the alias.
Which is why I don't have such a rule and would oppose it.
The attitude might have been something to do with the individual's SRE background. In that context, I understand the desire to ship small changesets that have a limited blast radius.
It's just not really practical for actually building software.
