I've seen some informal analysis that claims that the ubiquity of smartphones and the successful transition of the massive social networks to mobile is what specifically led to many of the alleged negative societal effects (increased political polarization, for example, although there are many other examples). The thinking goes that it's the all-day thumb-scrolling addiction loop on a tiny device that leads to these negative outcomes even more so than what was supposedly already happening with the pre-smartphone rise of social media.
Your mention of 2014 might be compatible with this line of thinking. Facebook famously abandoned its mobile HTML5 stack and "went all in" on mobile in 2012. They also acquired Instagram in late 2011, and WhatsApp in 2013.
I've seen some informal analysis that claims that the ubiquity of smartphones and the successful transition of the massive social networks to mobile is what specifically led to many of the alleged negative societal effects (increased political polarization, for example, although there are many other examples).
Of course you've seen such analysis, it's fairly ubiquitous.
But as the parent and the article argue, it's completely incoherent. Not that phones haven't given polarization and propaganda a bit of a push but because these things are just parts of long-term trends that need to be looked at. And a lot of the "social media opens people to evil" complaints came loudly from mainstream media who were understandably upset at loosing their semi-monopoly trend-setting (ie, propaganda).
Of course, a lot of the forces that effectively hacked social media were the extreme right, which I'd hardly a fan of. But this wasn't "a sudden rise in propaganda" but a relative democratization of propaganda. If you want a non-propagandistic way of disseminating information, you need to go much further back than 1990, probably look at a whole different method of communicating.
One other way to think about it is that a massive content fork started happening around the time of the internet.
In the "beginning", as the article states, there was the big 3 networks, and a bunch of fringe radio programs, and movie theatres, and newspapers. Broadly highly consolidated. A bit more emphasis on local things.
Then there was cable. You were certainly going to get more perspectives, but your age group is probably going to still only watch a few channels. And still radio and newspapers, and movies.
Now there's youtube, twitch, cable, crunchyroll, radio, podcasts, social media. 10,000 channels of content. You as an individual mix and match based on your own preferences and interests. Its also available everywhere. As is conversing with friends.
It seems like pure logic that it is much harder to create a consensus in a winner take all political system.
Your mention of 2014 might be compatible with this line of thinking. Facebook famously abandoned its mobile HTML5 stack and "went all in" on mobile in 2012. They also acquired Instagram in late 2011, and WhatsApp in 2013.