How do you square this with the observation that other fiat-backed stablecoins like USDC, which are obviously legitimate, are also printing massively?

It would seem to me that if transparent stablecoins with utility are going up, the simplest explanation for tether going up is that it serves the same role for people who have either become accustomed to it from its earlier availability, or have it as their only option due to jurisdiction. Not anything nefarious.

There seems to be little actual evidence to support conspiracy theories that Bitcoin's price movements are due to mismanagement of tether.