As a generalist, I agree with bulk of what you're saying but at least my personal experience seems to echo the fact that generalists in general are undervalued since when someone asks a person "what can you do for me", a specialist always has a better and sharper answer than a generalist - and that makes all the difference.
Personally I'll take a generalist any day since specialists suffer from the "if you only have a hammer everything looks like a nail" syndrome.
Having said that, my 1 career advice to anyone would be, become a specialist in 1-single thing, and then become a generalist in everything else. I'm not that, but I feel that that I would have been best served if I had been that.
It is used to describe a skillset which has a little experience in a wide number of areas (the top of the T) and deep experience in a single area (the stick of the T).
My experience is that opposite. I'm a generalist and every company I've worked for is looking for generalists. If you're doing boring business work, which most of us are, you don't need to know every crevice of any technology. The majority of software development is not moving the needle on crypto or search algorithms, it's crud business apps and reporting.
And yet... as 'boring' as those things are, I constantly see basic errors crop up all the time because people aren't even moderately versed in the technologies.
For example, you don't need to "know every crevice of a technology", but if you're doing LOB reports for business systems, I would reasonably expect you to understand what indexes are, or what joins are and how to use them, in your SQL engine of choice,
Personally I'll take a generalist any day since specialists suffer from the "if you only have a hammer everything looks like a nail" syndrome.
Having said that, my 1 career advice to anyone would be, become a specialist in 1-single thing, and then become a generalist in everything else. I'm not that, but I feel that that I would have been best served if I had been that.