I'd like to bring up one extra point in favour of as much anonimity as you can get:
What if someone bad knows you hold x BTC (or any altcoin). He knows crypto seedphrases are seldomly kept in a bankvault at the bank, but usually reside somewhere in your home. I wouldn't want somebody with a big baseball bat waking me up demanding the seedphrase of my wallet and threatening to hurt my daughter or my wife if i don't comply.
This woke me up since I never thought this might actually be possible even though I don't hold that much crypto yet.
KYC-exchange's databases get hacked on a weekly basis. If you don't cover your tracks, it's only a matter of time before some criminal close to you gets his hands on your address AND is able to track that you've withdrawn all your funds from the hacked exchange to the same wallet, and the funds never moved again... So he'll be able to conclude you hold x amount of euro's or dollars worth of crypto coins... Nothing is stopping him from using this info to rob you (violently if needs to be... He needs to find a piece of paper with some words scrabbled onto them, or he needs a password or pin to unlock your wallet... You need to be awake and afraid to give this info to him).
If you try to give your KYC info to as little actors as humanly possible, and always use a mixer/coinjoin/anon coin to hide your tracks, it'll be a lot harder for a criminal to get your address... And if he has your address he won't know how much crypto you hold, so he has no clue if it's beneficial to rob you, or if it's a waste of time...
Also, I never thought of the negative implications of KYC before also.