Thank you for the detailed explanation!

Being new to Nostr, I'm still trying to fully understand the relay concept and its possible implications:

1. What prevents esp. large relays from/selling relayed data to the highest bidder (data brokers, marketing/profiling companies etc.), and/ or hand over to a government agency if requested? Does it make a difference if a relay service is a paid service or free privately managed one?

2. Relayed data is all unencrypted Json, right?Ist it stored permanently on relays (like all BTC Txs/UTXOs on all participating nodes)?