To answer your first question:
I deleted the comments because they didn't add anything of value to the question itself. They were mostly a meta discussion that belonged here anyway. There is currently no feature that allows for moderators to migrate comments to a meta discussion or chat room. I figured that the same arguments about Not a Real Question and Duplicate would reoccur here.
To answer your other question:
Should I keep trying to persuade him, and, if so, how?
The answer the Should is rather uninteresting and could be based on any number of opinions. Popular opinion and demonstrated by the nine answers that all seem to say, NO it is not a good idea to push deadlines to take care of technical debt.
Furthermore not every answer is focused on Should... many answers like this one are specifically answering How which has been answered to death on the duplicate with 14 answers.
Beyond maybe a One Word answer, NO or YES, should wasn't that important in my opinion. The real thing the OP wanted to know was how to frame the argument to his boss to address technical debt. Should questions generally don't do well here because there is often wildly different opinions and perspectives for it be answerable in a clear way.