"Company culture" at Berkshire Hathway doesn't mean the same as at most companies. BH buys companies and don't interfere with them. So while BH employs upwards of 100k people, the people whose culture the CEO cares about is probably under 100 people.

This is the answer. While it is very real to talk about "employee culture" as company culture, in this particular case, the "culture" I was talking about was from a corporate/investment/acquisition level. Howards job is not to understand how each company that BRK owns is run, that is the CEO's job. But Howards job is to look at BRK from a high level and make sure that the CEO is executing in the same way that Warren set up, namely – buying companies and stocks at a "fair" price or below, and not micromanaging the companies that they acquire. If the CEO is not living up to that, Howard's (and the board's) one card that they can play is to replace the CEO.

sounds like a role that can be replaced by GPT