Because the leakers might have ethical standards? Same as with snowden not dumping everything directly and letting journalists scrub it first. None of this actually applies though because everything (supposedly) got leaked in the torrent.

Shady politicians are some of the quickest individuals to jump to lawsuit threats.

So the leakers may have already been under some pressure to not end up in jail for doing the right thing.

That's a weird take? It's entirely plausible to think that some of the info should be in the public (illegal stuff, prove of bad character, what's their strategy etc.) but not every PII in it? Like bank accounts, private addresses, private photos.

Probably because the leaker is actually the state, and in case the fact is discovered, they want to be protected against privacy violation lawsuits.