Developers are not making any new Gridcoin. The only compensation the developers get is through transactions from the foundation address[1] which only gets and has gotten coins from 1) people sending coins to it and 2) the one time transaction for unconverted coins from Gridcoin-Classic in 2014 (which was not a good idea in my view, but it's too late to reverse that).
The research does bring value because people can like the idea of receiving something that came from the fruits of scientific work. That has some degree of value to people even if not literal value you can exchange for. Speculative prices exist as with many things, but that is not the main purpose nor should be the main purpose of Gridcoin. I'd agree that no one should be trying to enrich themselves in this because that's not what it's about