None, absolutely none, of what you describe is age discrimination and you seem to actually know it, so stop calling it that.
Discriminating by experience is not age discrimination, it’s discriminating by experience because yeah of course it is.
No one is entitled to a job particularly to a job that they do not have demonstrable qualifications for. If a person does not keep their skills up to date with what the market wants they become increasingly unemployable. That’s not age discrimination. A person’s age does not affect their ability to learn and be curious about new things.
My personal experience contradicts all this. I am over 50 I’ve been in the industry for 30+ years. Personally I have never found it easier than now in the last 5 years to get good job offers. My age is never an issue probably because I can couple experience with a wide skillset and not just technical skills. I have and keep up my skills and am continuously learning new things and new technologies. Because of that, I’ve taken more technologies off my resume because I don’t want to work with those things anymore than most 30 year olds have on their entire resume.
Now continually learning new things is not for everyone. If a developer doesn’t like learning, they are in the wrong career. Go do something else. Expecting companies to hire inexperienced people and train them on a given technology when there are already people out there that have the experience just shows a lack of understanding about how the world works.
If you want to learn on the job, apply for internships, because that’s what interns do, not full time employees.
If you personally are having problems with “culture fit” type interviews I can tell why just from the tone of this article. You do not sound like a good fit for any team that I would want to be on. Unless I had few other choices you would be moved to the bottom of the pile regardless of your technical skills. You have written in this article a number of things that would have been giant red flags and immediately disqualified you had you expressed them in an interview with me or a number of other people I know.
Programming skills are only one small part of what it takes to be a good software engineer.