This doesn't really make sense, either. How do you not consider the right tool for the job? Do you just use whatever you learned to code and never really bothered to consider that you might be more or less productive with different tools? LSPs don't always offer a productivity increase in all contexts—they seem to be mostly useless for dynamic languages like ruby and lisp and javascript—but I have a hard time imagining a programmer that couldn't benefit from them in the right context.
And they're just a straight-up improvement from iterative compilation and ctags, the latter of which never really worked very well in the first place.