I agree not to go into low level programming expecting a wealth of job opportunities to suddenly open up, but I wouldn't tell people not to go there at all. Not only is assembly really fun to play around with, I feel like I've gotten a lot out of the bits of assembly I've read/written. Even though I've never written assembly code for work, being able to read the disassembly in gdb has come in handy before. Also, a lot of the subtleties of C/C++ never quite clicked for me until I had an idea of how the generated assembly would work.

It's similar to learning a functional language. I have no idea if I'll ever use Haskell professionally but learning a bit of it has been a good way to see problems and logic differently. I think both assembly and Haskell have made me a better programmer, even if I never become truly proficient in either or use them directly in my job.