Small by what metric? Would the publisher of The Griffon's Saddlebag be a small publisher by your terms? Griffon Macauley hit a windfall of $1.2 million on his Kickstarter for volume 2. His goal: $15,000.
The anticipated sequel with over 500 game-ready magic items, player options, settings, and more for 5e. Give out better treasure!
www.kickstarter.com
Now, I don't know what margin he was budgeting per unit he's producing and selling, but clearly that Kickstarter went WELL beyond expectations, none of which included suddenly having to pay 20% of that to WotC if he's forced to shift to OGL 1.1 because WotC pushes that license before his delivery of the product.
Yeah this is part of why I think that realistically there's going to be have to be some degree of climb-down from WotC on revenue %. If we look at DMDave he says they're usually looking 90%+ costs ("easily 90%+ of what comes in goes to contractors, cost of goods sold, taxes, platform fees, legal/accounting, etc.") which doesn't surprise me at all.
The response of course is "Oh well increase prices by 20%!", well for starters that doesn't necessarily add up maths-wise but ignoring that complexity, WotC have actually made this very difficult because the WotC-tax kicks in at a specific value, it's not a constant, which is a great way to trip people up, especially as it's basically impossible to incorporate into the way things like Kickstarter work right now (and strongly discourages anyone but the first $750k worth of custom!). If WotC had asked for 5% revenue at all levels, from everyone publishing commercially, that would be
rude, but it'd be fairly easy for 3PPs to incorporate it into their pricing structures and Kickstarters and so on. I think people would have grumbled and got over it, if that was basically all WotC were doing. People might even have said "You know what, fair enough!". Opinion could easily have swung in WotC's direction. And I suspect it would have made them more money too! There would have been criticism for doing it in an economic crisis, but I think WotC could have rolled with that.
What they're doing here may impact far fewer people, economically, but it's much more likely to cause a huge headache for those it does.
Which is I why I tend to see the fees mostly as arm-twisting to get people into individual company-specific licensing agreements and preventing future competition.
WotC are very aware of Kickstarters, I think - it's notable that when the Solasta Kickstarter was clearly going to succeed, WotC suddenly gave the Solasta team a special deal, where they'd been using the OGL previously. And I think if they see a Kickstarter going big with OGL 1.1, they may well actually be in touch with the people before those 30 days are up, in order to negotiate a better rate for them (assuming they've made agreements like that with Paizo etc.).
I still think that they really need to rethink the whole approach to royalties, even without deauthorization, to make this acceptable, but I also think they might. The only thing which makes me think otherwise is how downbeat Jon Ritter seemed about the whole deal (Kickstarter's games guy), so maybe his impression is WotC have really dug their heels in on this.