Question about Apple TV 4K (3. Gen)

Yes, of course, the new A15 chip is much faster, k smaller, has no more fans and the metal remote control is of better quality and can now also be charged with USB-C. But: you shouldn't buy the 64 GB model, it's quite a bad buy, because for only about 6 francs more you get double the memory, the Gbit Ethernet connection and the Thread chip, with which you can also do home automation at some point, if you want to, and the resale value of the Apple TV 2022 without these things is zero. I wouldn't buy one of those. I only recommend this model with 128GB of storage:
Apple TV 4K 128GB (3rd Gen) (Apple Siri)

Rather no. Your box will still run smoothly and if you like the current remote control, keep the old one. The environment and your wallet will be happy.