What about 2013 seemed more favorable to the fediverse than now? Twitter, reddit and Facebook were pretty useful at that time - I don’t think I’d have left.
Principles. That the whole internet and all of the freedom and diversity it can harbour was being monopolised by big giant corporations that had no interest in embracing an open web. Instead, they were convincing the world, especially those growing up in that/this era that the internet had to be constrained to the few walled gardens of big platforms.
These principles were as obvious and relevant then as they are now. Unfortunately convenience is a helluva drug. And, in the “Google” era of the internet (~2005-2020 ?), there was a certain naive optimism about big-tech and the internet, which no doubt lulled us in by its being “free”.
In reality, we all really thought that good and useful world-changing stuff was just going to be made for us for free. That the internet was going to inexorably make the world a better place. It was dumb and naive IMO and marks very well the failings of the Millennial generation (to which I belong FWIW). Unfortunately, it’s a lesson we had to learn the hardway. There were probably only a handful of people in the world that understood what the new industry was actually doing and was actually about and that had the philosophical will and ability to think it through and communicate to the masses what the choices we were actually making.