600m appears absurd. Are we seeing new hugely inflationary release clauses because of new money coming into the game? For the player, does it appear to be a sum so large it is not worth including the clause?
What's really absurd is La Liga is the only top league (from what I know) where release clauses are obligatory which put their clubs in bad situation and most of them have learned it the hard way. Not just Barca with Neymar, a lot of smaller clubs have lost important players due to relatively low BO clauses as well. RM have put 1B clause into CR and Bale's contracts years ago and something like 700m for likes of Isco and Kroos IIRC. Now most clubs are doing that as long as the players agreed on high clauses.
For me BO clauses in football at this point are just stupid and they're based on Spanish work law from 1980s IIRC.
OTOH you have Bilbao who have re-signed a few of their players (Muniain was the first one in 2018) with no BO clauses included in their contracts in recent years. Don't know how they did that but this kind of contract is for me much stronger than the one with a high clause as it really puts a lot of confidence in both sides to respect the contract.