> if you are a salaried employee it's because you're evaluated on your output and not the time you spend in your seat

This is just patiently false, it's common for salaried employees to have required hours.

https://www.inc.com/alison-green/my-employee-says-i-cant-sto...

Sure, obviously.

Your company can't just suddenly drastically change them on you without it being a constructive dismissal. This is not a new concept. Companies have been trying to dodge unemployment claims by making people's jobs so bad that they quit since forever. It's very easy to prove and will be seen as a firing by the courts.