Sounds like OP has more opportunity than the average person to keep skills up to date on company time.
Reading about Foobars at Scale isn't the same as working on them at Netflix or wherever. (Even if you try to put what you read into practice and it's somehow free/cheap to deploy at massive scale and load test it, it's still not the same.)
You’re right that conditions could be far better for skill improvement, though having paid free time is also a great environment (e.g. for potentially earning a graduate degree online from a reputable institution).
This is a real thing, at least for me personally. I've been self-employed for the last 4 years and have been lucky enough to live a very cushy life. I make twice as much now than any job I had in the past, but all my income is more or less passive and has nothing to do with how much I work. That being said, I know my current situation won't last won't last forever and every so often I get pretty stressed out at the idea of having to go back to a regular job. As a result I probably work 40-50 hours a week on other projects trying to find something else that will 'stick' in case my current income source disappears. It's still cushy in the sense that I get to pick and choose when I work and what I work on, but the thought of going back to a full time job, or god forbid an office, is pretty stressful.