Desktop to mobile was also a big shift from the perspective of wanting to offer the "continue your journey" experience + having the same experience on both. Which initiated moving features from being done locally to "log in and sync in our cloud", or dumbing features down on desktop, or downright removing them so that "it's the same on desktop and mobile".
Which IMO is related to the next thing in chain:
- It was really easy to subscribe to an RSS feed in 2000s; if you had a proper meta tag in the website header, the browser UI would show up a prominent RSS logo in the URL bar. Firefox had this built-in. Apparently Chrome too [1]. At some point this was killed. Perhaps due to mobile gaining traction, lack of space on mobile, and Chrome's annoying minimalist approach? Or perhaps because Google wanted to promote its own (R.I.P.) Google Reader, (R.I.P.) Google Wave, (R.I.P.) Google+?
(Having said that, I must admit I have declared RSS bankruptcy at some point, after subscribing to _way_ too many feeds).
- I remember there used to be a lot of blog platforms and discussion boards, people would write a lot of good stuff there, each of those platforms would create a de facto community.
Then, Google managed to make Blogger/Blogspot UX terrible; and most of other platforms died and got replaced with Facebook and Twitter. (I'm still not sure why many of those seemingly thriving platforms have died).
- Facebook and Twitter over years slowly change the algo, to not show you stuff you subscribed to, but random viral crap which optimizes "engangement".
[0] https://www.chromium.org/user-experience/feed-subscriptions/