tl;dr it's illegal to raise all your rents at once. RealPage use AI to add randomness, even though a simple random number generator would work better. Their goal is to trick the police, by making it look like landlords are raising rents independently of each other, even though they're secretly conspiring to raise them at the same time.

That's it. That's the only service RealPage provides. Nothing other than hiding evidence from the police, expensively. Antitrust legislation doesn't apply to them at all, though it might apply to the landlord scum.