Check out UniSwap and Aave if you haven't before. If those aren't compelling use cases, tell your friends to stay away.
I will offer some criticisms:
Aave - Earning interest on a speculative asset with counter party risk seems a bit silly. Most of the risk is bundled in the asset itself. If you invested $1,000 in a token as a small percentage of your retirement portfolio you're probably hoping the return is 20x. In this incredibly logical scenario 2% is meaningless.
Uniswap - It's cool if you trade tokens because it skips the extra step of sending the asset to a centralized exchange, trading it, and withdrawing it. The centralized scenario might actually be cheaper. Either way it's only impressive if trading tokens is impressive. And at this point it's not.
They both said some variation of “why would I want to use that?”
The product of crypto does a crappy job of selling itself.