Hi @voryzen,
First of all, I want to thank @ogra for stepping in and answering first. For those that don’t know, he’s the person who started Edubuntu all those years ago.
Secondly, you got the best answers possible from @Lech, who is definitely the go-to person on everything Ubuntu Pro-related, and clearly answered all of your questions and then some.
As far as where Edubuntu stands on the topic now, I speak for myself and Amy when I say we see this in a positive light. Without paying people to provide security updates to what are essentially dead/unmaintained packages upstream (meaning from the original authors), they’d be full of holes and vulnerabilities. If there was no way to generate revenue for the people now maintaining, then how would you sustain those people? Either way, it’s free for up to five computers, and up to 50 computers for Ubuntu members, and then there’s considerations for educational institutions as @Lech has already stated.
Interesting you mention that, because my wife (who is leading the Edubuntu project now) works in such an institution. However, don’t be fooled: even though it is a nonprofit institution, it receives government grants and operates an ECEAP program. That said, even though on the surface it might be private, it might still be receiving some government funding and meet requirements easier than you’d think.
Now, there’s one piece you’re not considering, and this is part of a larger conversation, and I want to be very clear here: all Official Ubuntu Flavors are not separate distributions from Ubuntu. They might look like it on the surface, they might seem like they’re separate, but they’re not. If you look at Fedora Spins, they’re more akin to that. They’re all under the same governance, and while they have their own sub-governance, they still have to meet a certain requirement to operate and receive the benefits of being an official Ubuntu Flavor.
This means they also benefit from certain items such as Canonical products like Ubuntu Pro, Landscape, and other products.
I hope that answers your question. Overall, I see Ubuntu Pro as a huge boon to every Ubuntu flavor.