Have you ever felt that you are loosing track of all new technologies on the market?
So while I think it is very important to read about and experiment with new technologies and languages, it's not bad to be part of the mainstream.
By mainstream I mean well-established technologies that are used for a at least a couple of years in production by a large percentage of people.
It's actually not that easy to find out what mainstream is in certain areas. There are e.g. StackOverflow statistics about what people ask questions but that may also mean that some technology is overly complicated or badly documented. You could look at GitHub repositories but that only covers the open source bubble of the industry. Then you could look at the job offers which represents mainstream the best in my opinion.
I myself work in the Java bubble (but this article can probably be applied to field of technology) and I remember when I read the Snyk survey. I went to through all the results and thought: "Well, we do pretty much what the majority of voters do". But I had the kind of feeling that we're "only mainstream" and not "bleeding edge".
It reminds me of some pop culture phenomenons. I think about the movie "Titanic", the book series "Harry Potter" or some pop music artists like "The Beatles". For all of those, I didn't want those pieces of art to be good because it was "too mainstream" (OK, the Beatles are not mainstream nowadays but I would consider it as a band that still a lot of people like) and I thought I'm just too smart for this (and I'm not).
But at some point in time, I decided to give it a try and had to admit that I really enjoyed it.
Although this analogy seems far-fetched, the point is that mainstream is by definition something that a majority of people (and that includes a lot of smart people as well) can agree on it to be good.
So, swimming in the main stream is not necessarily a bad thing. It means, that you will likely get a job and that you might know most of the technologies there. Keep on learning new things but don't feel bad if you're part of the mainstream.