Reading up on that, it seems similar in nature to our AvtaleGiro[1]. While indeed having my account number would allow a business to issue a AvtaleGiro request, it's just a request. I would then have to go to my (online) bank and approve it, including setting up a monthly withdrawal limit. So it can't happen without action on my part.
> They’re also the same numbers that appear on cheques, so someone could easily forge a cheque in your name with those numbers.
Cheques I don't know about because they were going the way of the Dodo even when I was young, but we did have BrevGiro[2] which was a way to transfer money. However it relied on the bank sending me serialized pre-filled forms, so someone would have to steal one of those as well to be able to withdraw money from my account.
However, many Americans do say on surveys that they are doing it. This happens even if they say their income is $200k/year. The likely explanation for this is that nobody knows what it means and are answering something like "if I missed a paycheck I'd feel bad about it".
https://twitter.com/besttrousers/status/1753260817389162516
A funny thing that happens with this discourse is that it comes up all the time, and every single time a hundred people reply those numbers are a trick because of outlier rich people, and then it turns out none of them know what a median is.