I got to thinking about why it is so hard to bootstrap a business in crypto and it is because NEW investors are always bailing out OLD investors which sucks up all of the capital. We can easily resolve all of this by placing unclaimed BTS from delegates INTO a yield fund for BTS holders. Having a yield fund would encourage people to move their money off of exchanges and to hold it for longer periods of time.
The side effect of a yield fund is that it wouldn't actually debase ANYONE except those who are looking to cash out short term. IE: transfer of value from those who want short term liquidity to those who are in this for the long run.
This adds considerable complication at the risk of not achieving the goals you want. As btswildpig mentioned, the exchanges can simply collect the interest (and design the BTS deposit and withdrawal process to maximize interest collected) and pass that interest on to their customers.
But if you wanted to implement something like this I would demand it be done better than the way BitAsset yield is done. First, the order in which people claim the yield should not effect the yield amount collected. The yield amount collected should purely be a function of the quantity of BTS in the balance and the time elapsed since it was last moved. Second, in order to not penalize delegate voters, updating a BTS balance's delegate slate should not reset the time. Furthermore, it should be possible to withdraw some amount of BTS from a balance and have the remaining BTS balance keep the old move time (so it doesn't negatively impact future yield on the remaining balance).
Personally, I don't think it is worth it.