I agree that changing the rules without warning was a bit unfair. However you should realize he unwillingly did you a favor: you lost 3k with 80 max bet, with 320 you would have bet 4x, with the same exact pattern most likely, and would have lost 3x4=12k.
Lowering the max bet only had the effect of slowing down your gains, so you felt like going on for much longer, eventually losing.
02:14:27 (1) so the change isn't permanent.
So, can I interpret this as: the change was made specifically for me? only because I always win (bit, and legit). I'm somehow disappointed.
You shouldn't: he has the right to lower the max bet if the house is taking too much losses and cannot afford. It's his business, he must manage it properly to avoid the risk of going broken. He lowered it while you were by far on top. Had he lowered while you were losing you could have had a point.
You and you only chose to try to win more under the new rules.