Actually, that's highly debatable. But I best not get into that.
It's not debateable in BattleTech. There is a reason the 'Mech is the king of the battlefield in that continuity.
And again, I'm talking about design reality, not informed ability. If game/novel/movie X tells me that Z is the greatest sword in the universe, and yet I see that it's design is logicly abysmal, then it's impossibly for me to take that seriously.
Reality check: Tanks are highly mobile. Take a look at abrams. It's fast, can cross over all kinds of terrain, has a low profile. It also has a very low surface pressure for it's weight and size, meaning it can cross terrains a mech would have big trouble with.
But I digress.
My whole point was that from a logical standpoint, mechs are less reliable than tanks.