The assumption that software can solve this problem is simply wrong. It's the regulation change that needs to happen if you don't want that renter pay the broker "services".
For example, a new law in Germany to apply the "who hires pays" principle for brokers in the renting market basically made the renting "broker fee free" for renters. Previously, the landlords would hire a broker that needed to be paid by the renter. Why not, it doesn't cost them anything, and at least they don't need to have a contact with the potential renters. Now, that they have to pay for the brokers service themselves, it's suddenly not that valuable to them.
For example, a new law in Germany to apply the "who hires pays" principle for brokers in the renting market basically made the renting "broker fee free" for renters. Previously, the landlords would hire a broker that needed to be paid by the renter. Why not, it doesn't cost them anything, and at least they don't need to have a contact with the potential renters. Now, that they have to pay for the brokers service themselves, it's suddenly not that valuable to them.