They weren't condemned for the algorithmic pricing part, they were condemned because they "participated" (subtext: along with other landlords).
The "algorithmic" part is just cartel laundering, they probably hoped that by not communicating directly with competitors, but instead having participants giving their data to "the algorithm" which would have consolidated the data and given each participant optimal pricing, they could evade charges.
I agree the title would have been much better if that point was clearer.
It's happening in more than just housing too. This also happens in food stuffs like potatoes.
If the major players in an industry all happened to share all of their data with the same consultant, and the consultant told them all what to set the price to, I imagine you'd have the same legal issue.