It has exactly as many practical uses now as it did then (not that many). However, it's full of a ton of bullshit, and some of it is dangerous bullshit.
Another thing that's as true now as it has ever been: you can easily learn the same stuff (and more) with a much lower amount of bullshit by going to the library and reading the more mainstream sources. They won't be written in as breezy or entertaining of a style, but they'll be much more dependable and comprehensive.
A chemist friend of mine once commented about the chemistry-related (particularly incendiary and explosive) things: if you really want to learn how to be dangerous, a wizard, or do really cool party tricks, your best bet is to actually learn chemistry more holistically. I bet the same is true for the other things in it as well.