Members of Congress shouldn't be allowed to accumulate this kind of obscene wealth - full stop. The only details up for debate is where we draw the line & how to aggressively enforce it.
They aren't "accumulating" it, they just have it. The top four, for sure, are wealthy from activities and careers prior to entering congress, often by a spouse or family.
Your rule would basically amount to "no rich people allowed to serve in government", which seems arguably even worse.
It explicitly isolates people with tremendous power from the levers of official power. That pretty much guarantees you'll have a shadow government. (A competing power centre. Less Q Anon and more gangs in South America.)
Your rule would basically amount to "no rich people allowed to serve in government", which seems arguably even worse.