This is not a good trend

Not at all. Ultimately, if you risk being sued for redistributing a piece of software (modified or not), it is unwise to redistribute it - why take the legal risk?

Also, this does not 'punish' upstream in the slightest. It simply gives them control over their project, if they wish to be the sole distributor then they can be by eliminating the middle man and thus protecting their reputation and project, in this way people are not redistributing it in a form they are unhappy with.

Personally, I'm against the concept of FOSS being treated this way, but I can see it is something some FOSS devs need.