Specialization (in anything) sets you up well in the future. Here's an example: Let's say you starting specializing in Go. One of two things will happen:

1. Go increases in popularity. You're then the go-to-guy for many projects and startups. You can consult like crazy and make a lot of money.

2. Go decreases in popularity. Many many projects still exist that are written in Go. Other programmers move on to the next flavor-of-the-month, and so Go skills become harder to come by. But these projects still need to be maintained and worked on. Businesses look for specialists to help them with this rare skill. You can consult like crazy and make a lot of money. This has been the surprising arc of languages like COBOL. COBOL programmers make serious cash these days, because the rest of the world has moved on.

So I'd say: Pick anything. Truly, just pick whatever you like the most, and try to be the best at that. Being a generalist just lumps you in with all the bootcamp grads and hobbyists. Being a specialist lets you offer skills/services that other's cannot. That kind of scarcity is future proof.