Didn’t Dan Allard self destruct his Valkyrie to try and kill/disable Yorinaga’s Warhammer?
Yeah, but again, that's another Stackpole classic. He really loves having action sequences reach an explosive climax.
Outside of the logic of early BT novels, it's the kind of tactic that is more likely to get you a discharge from whatever unit you're in, assuming you survive the ejection. Plus, at maximum you're looking at 40 damage applied LRM-style against anything adjacent to you (and then 20 the next ring of hexes out, and 10 at the next ring), which isn't likely to do much unless your opponents are already as bad off as you are. But hey, if someone wants to start a trend of being the BattleTech equivalent of the Pokémon player who spams Self-Destruct, more power to them, I guess.