Generally, I'd agree, that 40K - 50K is the minimum needed if one daytrades for a living.
However, say I don't need to daytrade for a living.
I have several brokerage accounts and only one of them is dedicated to daytrading, but I don't want to commit more than 10K or 15K + margin to daytrading due to the risk involved,( still means buying power of 20 - 30K - enough for a parttime trader swinging 500 - 1000 share lots of 15 -20$ stocks ).
I will now have to raise this daytrading account to at least 30K - but gaining buying power for 120K - much more money at risk if I use it completely.
If I stick with my risk-level and don't commit more than the original 10K - 15K , I'd have 10K - 15K in my daytrading account gaining a measily 2-3% money-market interest per year, while I could use it for other investments more efficiently and, most probably with less risk.
Instead, I will have to maintain a 25K minimum in a daytrading account just to have the freedom to daytrade as much as I want.
What a ridiculous rule. Could be invented by a german bureaucrat.
Can't see any of the intended "benefit" for the small traders in this new rule either.