Progamming language evangelism is basically a zero-sum game.
Some languages don't really intrude on one another's territory — e.g. not that many people are rewriting Ruby programs in Rust — but some very directly compete.
So if you want to convince someone to use F#, you have to convince them it's significantly better than some other closely-related language. And that's hard!
I have a strong suspicion that the next decade will see a reduction in programming language diversity. JavaScript/TypeScript and Python will become even more popular, to the detriment of everything but Go, C++, and Rust.
Platform-specific languages like Swift will persevere, as will Java, which is unkillable, but the vast array of languages will become less vast.
Some languages don't really intrude on one another's territory — e.g. not that many people are rewriting Ruby programs in Rust — but some very directly compete.
So if you want to convince someone to use F#, you have to convince them it's significantly better than some other closely-related language. And that's hard!
I have a strong suspicion that the next decade will see a reduction in programming language diversity. JavaScript/TypeScript and Python will become even more popular, to the detriment of everything but Go, C++, and Rust.
Platform-specific languages like Swift will persevere, as will Java, which is unkillable, but the vast array of languages will become less vast.