It seems that Verlinde's emergent gravity model would be explainable if one assumes that the cosmological horizon is very slightly gravitationally repulsive.
This would explain the galaxy rotation curves. The result would be similar to MOND.
Is this the case?
For a lone body, no such repulsion can exist. Each body has its own cosmological horizon. But could it be that a body near a large mass is pushed by the horizon towards that large mass? Obviously, the effect should be small and be noticeable only for galactic distances and large masses.
In other words, could it be that the cosmological horizon creates a very shallow effective potential that rises a little bit at its distant position?