Can we really assume the social media we know today would exist in it's present state without advertising? I think it would be inconsiderate and wholly unimaginative at best to suggest that it would. I think separating the two is a mistake.
The internet forums I grew up with in the late 90s were, I would argue, nothing but healthy. They exposed me to worlds of encouragement and knowledge. The social media we have now seems to be no comparison.
"Making people watch ads" is not the problem with advertising. The problem is the existence it creates for ourselves. Advertising, at it's current levels in the US, dictates our whole conception of the world we live in. I wonder if many will ever realize this without studying humanities and working in the ad industry; two things that combined have depleted my faith in humanity unless we can reverse this grave mistake. To think this is just an issue of time lost sitting through ads is just a misunderstanding of what advertising in 2018 even is, or of how it defines the world you think you live in.