How about an app that collectively bargains rents algorithmically? Call it RedPage lol.
That's basically a listing search page that allows you to sort by price.
What else do you expect "collective bargaining" to do in a market where every tenant has a different landlord? Your landlord isn't going to care if the tenants of 10,000 other landlords threaten to move out. They only care if you threaten to move out, and then to credibly do that what you need is to show them the unit you could move into which is asking for less.
The real problem is that you need the unit you can threaten to move into to first exist, rather than its construction being inhibited by zoning etc.
Collective bargaining your landlord can't ignore is you and your neighbors all withholding your rent payments until your leases are renegotiated.
There is such a thing as a Tenant Union, and in fact they are currently spreading across the country as renters turn to collective bargaining. It works!
That doesn’t work you all get sued and hit with a judgment to pay late fees