Ubuntu freeloaded on Debian so its fairly reasonable to consider the ubuntu skin to not be worth having if the result is advertisements being pushed onto users.

Companies that want to freeload on a free software community will always have a hard time. They may be praised in the beginning if they bring fresh and new energy, but trust is only going to work for so long until the "monetization features" starts being pushed. Historically that only works if the company reforms the original in such a way that it essentially is a completely different thing. Ubuntu today is still just a skin over Debian that users can easily replace.

Accidentally the best thing Ubuntu brought to Debian was the release schedule, which the Debian community adapted. Without that advantage there isn't much point to Ubuntu unless Canonical continuously pour a lot of money and developer time for free into the ecosystem. A lot of people commented at the time that such a thing wasn't sustainable.