1) I went to community college, dropped out, then finished my degree at a state school 10 years later. Google didn't care.
2) I have no idea how long it took them to decide to interview me. Once they decided I got a call. People I've referred recently have received _very_ prompt responses, though years ago sometimes people would sit "in the system" for a while.
3) It is good to brush up on algorithms, like for most other SWE interviews. You do end up using this stuff regularly though - Even if say, your'e "only" doing UIs, it's how you avoid accidental n^2 algorithms in the middle of your UI code which pisses off your users. I don't get the attitude that algorithms are just academic. They matter. Besides, "use a hash table" is often the correct approach in interviews and non-academic code ;)
4) I have no idea what a Fermi model of golfballs is, but I've never asked or been asked such a thing. And "fail" is such a black and white term. Candidates are scored, and those with marginal scores the first time often get another chance later on.
5) Not my experience in general. Sometimes the interviewers lag on getting in their feedback for non-hires, which is really unfortunate, but the recruiters are pretty on top of things.
You say your post is based on actual hiring experiences, but I bet that the negative experiences get much more attention than the positive ones. People don't generally write blog posts about how wonderful their interview was.