This isn't true in Australia at least. Banks wear the cost their side for the new business and enjoy when people go direct to them for the lack of fee paid.

The broker issue is stems from they wont look at loans that dont offer commission, these are often cheaper. And potentially an unethical one will push you to a worse loan that pays them more.

IMO brokers have a much more limited benefit these days with easy to use comparison sites but still serve a purpose for more complex transitions and people that are low in financial literacy.