I think the point here is that Linux distros are not immune to the business tactics of proprietary, commercial software. Ubuntu has just tested the waters, and end-users need to keep on their toes.
Given that the industry as a whole is moving towards the model of giving everything away for free and profiting from data mining, it won't be long before sponsored ads and opt-out become the norm in the world of FOSS, too. Yeah, it's nice that if a FOSS project turns bad it can be forked. It's nice to say that the efforts of the distros don't affect the kernel itself. However, "Linux" itself isn't useful for much outside of servers and embedded systems, so almost everyone using this OS will be getting a distro, and that requires people to make educated choices as to which distro they can trust.
Lambasting people's concerns as mere FUD isn't going to help. There's real reason to worry about this stuff.