Still as relevant in 2020 as the day it came out. This OSR is a classic among the hacking community. Many OSR systems have been created based on this ruleset. This book has tons of applicable GM advice, monsters, and optional rules. The amount of add-ons for TBH is also amazing. I purchased The Unearthed Hack as well, I recommend you do the same to use it as an "expansion pack"
[5 of 5 Stars!]