I don't know what happened between Chinese communists and utxo but he was definitely a bottom.
About relays. Could be anything. Spam protection, bad code, client bug.... It's hard to know without logs. For example, in my case, NextDNS may be the cause of the problem.
nostr:note1cydxwdagqg9qq94hhyfdw5qcz9tgvvj60m076y695hwwz4c672ls3wju8p