Really wish there was a link to the site they tried for every "dead" site, if only to see the goodbye notice that pages put up. Sites like "Our Incredible Journey" [1] really highlight just what happens to so many of these companies, but an unreachable domain is definitely not a main criteria to base a graveyard off of.
Yes definitely. I just followed the steps over at https://kindlemodding.org/ and got my Paperwhite running beautifully and with more customization than ever.
Seconding the recommendation for Apollo. It's definitely a shock to get used to at first, but it's so customizable that it reminds me a lot of RES if there was a mobile app version of it.
Stadia has not been cancelled, they just shuttered the internal development studios. The service itself is still alive and getting new games frequently.
While true, there's an alarming amount of products on eBay that are just drop-shipped from Amazon. By avoiding Amazon, you have to avoid eBay as well, at least in terms of buying items that are new.
[1] https://ourincrediblejourney.tumblr.com/