I don't think it's a coincidence. A lot of the value comes from things being open and free, which enables rapid proliferation and ubiquity of the technology, but also drastically increases the complexity of making money out of it.

It's one reason I'm really not a fan of the Silicon Valley model .... pick out the top 10 most important technology advances in the last 20 years and about half of them were uncommercialisable in the Silicon Valley sense.

Sun made big money with Java through licensing. Any Java-compatible implementation vendor paid big money to Sun (including IBM, Azure, etc.).

Was that really "big money"? How many vendors were there, and how many licenses did each end up paying for?

If you wanted to write your own JVM or port the JVM to a different OS you had to pay something like $1M. I wouldn't call it big money because there aren't that many OSes. J2ME phones also paid royalties (which led to the Android lawsuit).

Plenty through the last 20 something years, some of them still going on.

https://en.wikipedia.org/wiki/List_of_Java_virtual_machines

Google is the only one that worked around the licensing, and now we have our phones stuck on a mix of Java 6 - 8 subset.