In my perspective, in 1946 they started to simplify everything. Before that, the animation was more realistic. And then in 1949 it started become more "fast"-paced. Then Gene Deitch made it a freak show, he made Jerry a prick that would torment Tom and make everything his fault so his owner would abuse him. I know it's a cartoon, but that just seemed sad IMO. Some even seemed scary and disturbing, I remember when I was a kid I got really disturbed and scared at Tom's new owner during the Gene Deitch era. I will give him credit however for making Carmen Get It!. It had alright animation, the sounds fitted, the music wasn't so damn weak and HE ACTUALLY got the formula right for once. Seriously, it took him 12 episodes to get it right? I think I remember him saying somewhere that by the last episode he was finally starting to "get it" but then the show got cancelled.
Except for at 2:46 and 3:48, I hate those bits.
Gene Deitch said he hated Tom and Jerry for the amount of violence in it, maybe he made it shit on purpose? Or maybe it was shit because it was done in Czechoslovakia? The Chuck Jones era had better animation, but shittier drawings. It was overall alright.