No objections here.
These aren’t obligated paid mods. Anyone can still do free mods that rely on Nexus for downloads and stuff.
If anything, this is like FDroid / Google Play Store with FOSS apps. You’ll find dozens of paid foss apps on the play store that are free on fdroid. The play store is for donations and convenience. Auto updates without modding your phone, centralized store, etc.
If you refuse to buy on Epic, you send the message that you don’t like to buy from Epic.
If you refuse to buy after it hits steam, then you’re just 1 of several billion who didn’t buy the game.
Why would you continue to not buy?