I agree that people who think they can do this will eventually lose money, but new investors don’t know, and if their first reaction to “discovering” this arbitrage is that they have lost money, they will have a bad sentiment towards the project. Eliminating this possibility with dynamic rebasing means people only see the project, and its potential, for its actual value as a long term play.
When I first saw all the AVAX forks, I planned to write bots to cycle around and collect rebases just like many others who’s intial instinct is that it is profitable, but in the end calculations it is not.