What’s the point of an emergency fund I have *enough* in my brokerage

What’s the point of an emergency fund I have *enough* in my brokerage Let’s say I have 24 months’ expenses saved up in my brokerage. With the standard advice being 6 months saved in your emergency fund, I have 4x as much in my brokerage. So even if the market took a downturn, there’s no way it would drop by 75%. If this is my situation, what is the point of a separate emergency fund in a HYSA? The common argument that I’ve heard is: “if there is a downturn, you wouldn’t have to sell your stock”. But conversely, if we are in a bull market, as we often are, I’d just be losing gains at that point, right?