Getting Epic’s money isn’t a slam dunk for profit. You’re hedging your bets taking guaranteed Epic money for lower potential sales vs non-guaranteed Steam money for higher potential sales. Having a bad exclusivity deal on Epic and then selling your game at a loss (90% discount) on steam isn’t profiting both ways, and sometimes isn’t profiting either way.
I also disagree with the sentiment that you’re reinforcing bad behavior. If anything, you’re signalling to them that you won’t support exclusivity deals, and are happy to wait for a deep discount on Steam. Ultimately, that’s a win for consumers.
That said, fuck exclusivity deals, and I’m much in the same boat where I’m hard pressed to support developers that take them.
It’s less money in their pockets and more money in ours. That’s not going to be a double win in their books.