Look, if SkyUI were not free, Bethesda and Valve would never have gotten the money for Dawnguard and Dragonborn from me. I simply would never have gotten engaged enough to care. Anecdotes aren't data, etc, etc, but there it is.
EDIT: There's no obligation to supply nice things for free. But that doesn't mean it's not a good thing.
SkyUI is still offered for free, just not the next version.
Could that cause compatibility issues with other mods in the future? Possibly... but if SkyUI releases a paid update which breaks people's favorite mods, it won't sell. And I doubt that many mod authors are going to buy SkyUI just to make sure their mod works with the paid SkyUI. Basically it falls on the SkyUI team to be careful with their changes (something I'm sure they're used to doing, as breaking compatibility is NOT a NEW problem)
All the claims that Steam is "stealing" mods from users are... frustrating. Can we agree that the people saying *that* are entitled morons, or at least misinformed by early... misinformation?
Because all Steam is doing is offering mod authors an option to monetize. It's not an attractive offer, but it's just an offer. If an author decides to take advantage despite getting a 25% cut, it's not Steam nor Bethesda's *fault*. It's no one's fault, but it's the creator's decision. Apparently they want to be compensated, and for some reason think that this 25% will exceed Paypal and Patreon donations.
Put another way, the author thinks think they can force users to pay *over 4X* as much money than the amount that gets donated. Despite all the easy avenues of piracy, and all the bile and blind hate flying around for anyone who dares join the system, some creators are thinking "Yes, but my compensation will be closer to what I deserve". People keep stereotyping modders as saints who don't want compensation, but what this has shown is that many modders (by no means all, but many of the most dedicated) simply had no way to get the compensation. They wanted to get paid, but couldn't arrange it.
So if you want to blame someone, blame the users who didn't support these creators enough through donations.
Or, blame the creators for setting unreasonable prices. That's certainly your right as a consumer, you don't have to pay. Though the mod author never owed you a thing.
Or I guess blame Bethesda for selling the game with the implication that the community would fix, finish, and totally convert the game for absolutely free. Which happened for 3.5 years for Skyrim, TWENTY THREE years for TES series in general. If it's suddenly a boycott-able offense, feel free not to buy the next installment.