Was just quoted $1500 from Firestone to repair my a/c. They said the a/c compressor is seized.

A little history. The car has 172k miles on it. The a/c was very weak on a recent road trip we took. So in desperation, I recharged using a can and kept it in the "green" area of the gauge, even though it was already indicating green before I even charged it. So I may have overcharged? In any case, also remove the cabin air filter. It was completely clogged. This was the most likely culprit. 300% improvement after that, and we got through our trip comfortable. Fast forward 3 weeks later, and I did a few high revs accelerating w/ the a/c on. The a/c almost immediately stopped working after that.

I just went outside to check and I can move the compressor clutch by hand, but it gets a little bit harder to turn once in each rotation. Is that normal? I figured it was just moving fluid in that one spot.

Anyway, with the a/c on, I see the condenser fans kick in, but the clutch never engages. No strange sounds or anything.

Any suggestions on what I can do next to diagnose? I'm happy to replace parts on the compressor (clutch, bearing, pulley, coil) as I've done lots of work on my past cars, but anything more where I have to remove the lines and it's likely too big a job (will probably just sell the car as is).

I appreciate any help or guidance anyone can give. Thank you!!