wait, what tournaments are there when one's got 100bb late game?
There are situations where it's good, but for the vast majority of the time, it isn't. It's a advanced play, that needs advanced reasonings to do so, just play tight from EP, TT+/AK for 9max and 77+ AJs KQs AQ+ for 6max, widening the ranges when there's big fish at the table especially when there's ones in the blinds
and the idea of almost always opening for the possibility of staking, that's just bad advice, assuming you're talking about 9max, 6max can be good with antes involved. There's this theory called ICM, and basically it goes 1 chip does not = 1 chip in a tournament, and the more chips one has the bigger the difference. Opening SC from UTG in 100bb cash games as a standard in 9max or 6max is just a losing play, there would have to be a massive skill difference to pull it off and going by OP, do you think this guy is super skilled?