In the early Gen 8 OU metagame, suicide Stealth Rock lead Excadrill used it to stop Defoggers from removing its hazards. It wasn't used to do damage, it was used for the recoil itself. Right now, it doesn't see major viable use except on Magnezone. Steel is more of a defensive type, so losing 50% of a Pokemon's HP is usually unwelcome in most cases. Most dual-type offensive steels like Magearna usually don't use Steel type moves at all since there are much better options (Steel is a pretty bad offensive type, with only 3 types super-effective against it and 4 types which resist it, all of which are common in the metagame). Lets say a Magearna did for some reason run Steel Beam. However, that would basically be asking Heatran, Magearna, Assault Vest Melmetal, Excadrill, Corviknight, Cinderace, Slowbro, and Toxapex to switch in. One wrong prediction with Steel Beam and you're pretty much screwed.