You can still do it too, but you need to see through the fad and not go for the shiniest technology out there. I've been reading "The Design and Implementation of the 4.4BSD Operating System" because it's basically the best explanation about OpenBSD as it (and NetBSD) still follow the same general architecture.

Another book that's worth its weight is "The Linux Programming Interface" and "The TCP/IP Guide". Also you can probably buy "The Go Programming Language", "Programming Erlang", and "Programming Clojure" and still come ahead. As long as you choose to learn technologies that have thoughtful design, or has a standard (even a de-facto one), you're golden.