I'll add the very first program I wrote was in octal entered via the console of a CDC 1604.

Yes, I'm really that old.

Back in 1997, I lost a very lucrative contract. I was 56 at the time. I went looking for work and not a single one of my efforts was responded to. I finally found a job for less than half of what I'd been making. The job entailed web design and development. I was an expert in network design and development at the time. But, any port in a storm is better than not working.

I had a new boss that let me figure it all out, i.e., he valued experience, even if not directly related. Then he resigned for a better position. The second new boss didn't think old guys were worth anything. At one point during a meeting he said, and I quote, "Why should we listen to you? You're retiring soon." Then he quit too. The third boss was another old guy. He let me do what was needed to get the project complete. As far as I know, it's still running.

11 years ago I retired at 65, and am now completely obsolete.

In my opinion, there's two sides to ageism. One, if the old guy (that's a gender neutral term if anyone is offended) keeps his skills current, and is willing to learn, then that guy is a good candidate for whatever job being offered, even if the guys current skills aren't relevant (I stand as a good example). On the other hand, someone who's just waiting to retire and not keeping up with technology, is a waste of time and money.

The guy's family had been grazing cattle on that land since the mid 1800's. The law that created, and gave all that land to the BLM was enacted in the 1930's. I's say the guy had a claim to the land much more senior than the BLM. My brother-in-law's family has been ranching on the same land since 1856. He feels the same as the guy in Nevada. His family has protected that land since long before the government claimed it was theirs.

First some context. I'm 70. I learned HTML, Java, C++ after I turned 50. I learned PHP at 64. The more languages you learn, the easier they are to learn because every language does essentially the same things. So learning a new one only involves learning the differences from the last language you used.

I would say "follow your bliss" is the only way to be happy in your job. I tried management, didn't like it and failed; not because I was doing a bad job but because my heart wasn't in the job. So, I found a programming job when I was 56. It didn't pay as much money, but it I liked doing it, and kept the job until I retired; getting outstanding reviews every year.

Number6.2 reasons are wrong.
1. Nobody is old who believes they're young. Granted one doesn't has as much energy, but that's what coffee (or your favorite stimulant is for).
2. Expensive is relative. As long as you get enough to support yourself and your family, plus a little to save, you're earning enough. By the way, I have a CS Masters also and 35 years experience, and was used to earning 6 figures. So going to a salary less than half what I had been earning was difficult, but, it wasn't impossible.
3. Knowing all the tricks and calling your manager on it, is just an excuse to be rude. One of my managers in my last job was one of those assholes. I just kept a copy of the book "How to Work for a Jerk" displayed prominently on my desk. He didn't last long. When I finally had enough (He called me a liar to my face at a staff meeting), I followed the "Open door policy," most enterprises support, all the way to the top (in my case the Chief Justice). The investigation that followed vindicated me and cost him his job.

So keep on trucking, and doing what you like best, i.e. Follow you bliss.