Well it's not entirely nothing. They are going to be the handlers for payments as well as inevitable refunds.
So nothing then since the entire process is automated.
It's not an inherently bad idea but you are correct in that they need to work for it. The biggest problem on Steam's end was that they don't validate who owns the content so, to quote from last time, "what's to stop someone ripping a mod off Nexus and posting it to Steam?".
Nothing, that's exactly what was happening and is exactly why the entire thing got shut down and if Greenlight has proven anything Valve have no interest in validating or QCing any content that goes on their store front to check weather it works or that it is even the author's original work.
They need to have a content control system that actually gets worked through and a way for the original authors to make sure they can validate their work. They also need to make sure that the work is original and not ripped from other games otherwise they're gonna be at the wrong end of a Cease-and-Desist.
Greenlight, if Valve can't be bothered doing that for a system designed to deliver entire games they sure as hell ain't gonna do it for penny and dime mods.
Biggest problem for Bethesda (since it was Skyrim that started it) was that they were taking a massive cut for, like Valve, little to no work. Maybe they provide the tools and the engine but do they really deserve that much when the game engine's cost was recouped by people purchasing the full game to start with?
No Bethesda shouldn't have been getting a penny from the paid for mods saga.
The entire debacle with PS4 mods shows that Bethesda were willing to do even less work than Valve for their chunk of change. The reason the entire system on PS4 was held up was because Sony wanted Bethesda to vet the mods for content prior to them going up and Bethesda simply had no interest in doing that. The other issue is that it introduces a worrying trend and the fact it was a Bethesda game that intro'd this shit show of a system is good. All the games that have used Gamebyro; Oblivion, F3, F4, Skyrim have then gone on to have extensive community generated fix mods that resolve the issues that Bethesda either couldn't be bothered or were unable to fix via patches. What happens if that mod author decides to charge for that mod? Bethesda are now getting money for a mod that fixes their broken game ON TOP of the money they got for selling the broken game in the first place. It's a system that promotes the developer to not fix the broken game they release.
Will they be maintaining the game with updates with this new funding strategy or will it be funding the next installment? A little transparency explaining why they wanted a cut would help.
Bethesda will no doubt use some EULA small print non sense that says a modder isn't allowed to profit from their work but if we take a cut then we are alright with that but the reality is they are just even greedier than Valve when it came to this, at least Valve provided a store front (even if it is utter shite) and server hosting, Bethesda provided fuck all.
I mean what needs to happen is either they give a fairer cut to the authors (either 33% each or 50% to the mod author and 25% each for Valve and publisher) and reveal how much work is on their ends (Valve/Steam and respective publisher) OR better; have the mods be free for everyone to use and use a donation system much like Valve already did with their stamp system in TF2 for community maps that made it into the game.
A donate system, from which Valve takes a percentage that is just enough to cover the hosting fees with an additional 1% to cover whatever costs they believe is included. If Valve on the other hand do implement some level or form of QC on the mods system then they can maybe increase that value to 5% on top and the publisher of the game gets a big fuck all from it, UNLESS they are actively involved in implementing and operating the service on a day to day basis.