I think this sets a dangerous precedent. Till now it seemed that the desktop was the last mainstream open computing platform due to it's legacy rooted in standardisation, but that seems to be moving too. While iOS anyways treats users as clueless and prefers being their "savior" instead of giving them power, atleast their attitude can be justified in that mobile makes computing available to people who have no time for understanding computers and need to be protected. But I think even iOS doesn't intercept your downloads. Neither does Android, the business model of which is supposed to be forcing people to consume Google's services.

If an OS will intercept your download, and guide you towards a "better way", how will a competing product even gain marketshare.