That's a lot to read through but I think I get the main idea.
One thing that's sticking in my head is that it sounds like they're pulling two rather scummy stunts, but also stunts that can backfire spectacularly on them.
My way or the highway:
As stated before, if too many people choose the highway, you just screwed yourself. I've played other systems that have nothing to do with D&D just on these boards. I've seen others. WotC does not have the monopoly on tabletop gaming they seem to think they have.
We're a big corporation, come at us:
This is the thing that pisses me off more than anything. They do something legally dubious at best and more likely straight up illegal (predatory in any case), but since they're a big corporation with lots of money, what can be done?
I mean, hopefully a class action lawsuit can be brought against them. Maybe some of the bigger "small businesses " can give a bigger fight than WotC anticipated.
Unfortunately, big companies like this more often than not will survive these class action lawsuits while the smaller businesses are forced out of business.
Best thing I can say is that WotC's reputation is ruined and hopefully this will backfire on them more spectacularly than they could have imagined.