I'm curious, why does demolish need a buff?

I'm not saying it's horrendously overpowered, but why exactly do you feel the need to buff demolish? Is it underperforming? I see almost every tank take this thing, especially gigacancer tanks like sion, chogath, etc. that are strong enough to easily shove many top laners into their towers.

Under what insane gameplay view is this rune underperforming?