But seriously tho, what's the big deal. Valve's been allowing people to create paid mods for their Source games for a long time and nobody's bitching about it. Modders who are in it for the thrill are still releasing their shit for free. Skyrim's workshop and the Nexus site will still be where they are. All that Bethesda is implying is that they're willing to "upgrade" some mods to the semi-official DLC status, which is p cool, since there's going to be certain quality standards, they can't promote obvious schlock and smear their own reputation.
But eh, seems like the most obvious reaction is to get mad about it.
The original paid mods attempt was opposed for two reasons:
1) The ideological argument - "Mods should always be free! You are encouraging greed and destroying our communities!"
2) The "market regulatory" argument - "The average mod is worse than the average game, so why would you let anybody release a mod on Steam with no gatekeeping whatsoever when you don't allow the same for games? Unleashing a torrent of shit on the market is bad for consumers."
This addresses #2. It'll be interesting to see how it works in practice. If the gates are kept high enough, people who claim to oppose paid mods because of #1 might find out that it's not so bad after all.