If complete history is visible for each Bisq node then this is affecting the privacy negatively in my eyes.
Just a theoretical scenario:
Bisq user U had transaction selling 0.25 BTC for €1751.37 at timestamp t and receives the Euro on his SEPA account. He forgot to mention this trade on his tax declatation. Earlier or later the finance administration will scan the decentral exchanges and will find a transaction with €1751.37 at time t, the same they saw already on U’s bank account with purpose “AB34HFK” which they didn’t understand in the first place.
Already now there are companies offering to public administration services to translate the Bitcoin addresses into real names and those or others will do the same with bisq & friends.
Could the history be encrypted/hashed, something where the node has a kind of prove that the transactions happened but showing only the own transactions in clear language?