Compare this with C. There is a degree of serious technical focus that languages like these demand for big projects. Embedded systems, Operating systems, Databases, compilers etc. A big part of software world uses these languages on a daily basis. But there is no where the kind of hipster crowd, these languages have the web frameworks or languages have.
Even if you spend some time searching for resources on the net, there are few that teach deep C skills. There might be one or two books out there which haven't been updated in 2 decades.
By and large, these are unfashionable fields to work in. The barrier to entry is really high, Success comes only with seriousness and application of well focused effort, mistakes are expensive and they warrant serious RTFM'ing the hard way- to write to some real serious code.