Re: internet advertising was rendered ineffective
No thumb as I think this is different issue. Trackingless advertising wouldn't be ineffective, it just wouldn't be personally targetted. Advertisers could still choose sites based on contextual content, e.g. wool vendors could place their ads on sites with knitting patterns. If this didn't work, commercial tv wouldn't exist, either. It still works, just not with a privacy problem.
The benefits of personalised advertising are doubtful, particularly when so many of the anecdotes are along the lines of "I just bought a fridge, why do I keep seeing adverts for fridges?"
Start-ups don't necessarily rely on advertising. Some dominant players with advertising revenues crowd out alternative services, including from start-ups. Who's going to fund a FB or Google killer now?