This problem is hard to solve at the root because each MLS is independently owned and heavily influenced by the National Association of Realtors and local governments. As an active RE investor myself, I'd love to work on a problem in this space.
You hit the nail on the head. Having developed with MLS data before, my opinion is there's little incentive for MLSs to make the data easy to work with. As long as each MLS gets their data distributed on the large portals that most consumers use, there's little reward to update (read: spend money on) their systems to implement a modern format to help indie developers and startups. That's the status quo. I don't think anything is going to change unless the large portals band together and spearhead some kind of industry-wide effort to fix this problem.
As an aside, I'm working on a RE investment product that solves challenges similar to this one and I'm looking for RE investors to join me. If you're interested, shoot me an email at hello[at]myname.com.
This problem is hard to solve at the root because each MLS is independently owned and heavily influenced by the National Association of Realtors and local governments. As an active RE investor myself, I'd love to work on a problem in this space.