Similarly if you sell shares in 1 symbol and buy shares in another in less of a time frame than a few days you aren’t using cash. You are using credit (because it takes days for sales to settle).
All of that credit risk is all currently legislated to go through a few bottlenecks who have the power to enforce their own credit rules.
Analogies are dumb but it would be like if Amex called all the casinos and said “everyone has 90% less credit than they did 2 minutes ago”. If you had a roulette ball running based on your previous credit line at Amex you can bet the Casino would grab that ball. Especially if it had 200k Amex lendees in their pits.
That is not what I'm talking about though. I'm talking about 100% cash.
If you are trading on margin you can get margin called. If you aren't though your broker has no right to do this kind of stuff.
You are suggesting the casino would grab the ball for people who were not using amex. Deeply illegal.
I suppose you could make that argument and if you wanted to encode that as law I wouldn’t vote against it, but recognize it’s going to manifest in brokerage behavior where you can’t trade as fast or you have to keep more cash in your brokerage account.
[edit] I’d also love for you to cite what law a casino would be breaking by shutting down a game mid roll because I have no direct experience there but my mental model is that Casinos have wide latitude on allowing the games to run or not.
I don't understand your argument. RH either has the money to put up collateral or they don't. They didn't this week. That seems like the end of the story. They can't just "choose" to have more cash on hand than they actually have.
Your only real job is to operate fair and unbiased bid/ask spreads and execute trades fairly. If you aren't going to do that then you are running a scam on your customers.
How is this fundamentally different then you placing a bet at a roulette table and the casino changing the rules mid-spin to make sure you will lose?