Where are you? We have tons of 2-lane roundabouts in Sweden as well, and I can assure you that far from everyone understands them. And even if they understand them in the sense that they got the theory question about them correct on their driving test, everybody certainly doesn't implement that knowledge consistently and correctly when faced with a 2-lane roundabout.

Traffic police here in Romania had to actually add some stuff to the legislation that would make 2-lane plus roundabout traffic easier to understand, the reason being that the traffic policemen themselves had conflicting opinions about who had the right of way inside said roundabouts (when changing lanes, for example).

Our town has loads of them too, and everyone think they understand them. Still accidents are common because people think it's ok to just go straight through by changing lane to inner and then directly exiting without yielding to the ones crossing their path in the outer lane.

There's lots of multi-lane roundabouts in the UK, and generally seem to work well, but they're often inconsistent with how lanes merge or depart.

One that gets me every time I go past is one where there's like 20 signs saying that both lanes continue to the main road to the right (270 degrees around, the UK so driving on the left), but I don't think I've ever been through there and not have someone try to merge in to me trying to get into the left lane to exit, despite both lanes leading to that exit.

I agree, Australian cities seem to think that they solve every traffic issue. There is a double lane less than 200m from my house.

The shitty part about roundabouts is when people allow blocking of the view to the right on the round about so you are unable to see incoming traffic till its almost on the round about.

The number of drivers who think you can freely exit from the inner lane suggests otherwise.

Honestly, even looking at a picture showing how a 2-lane roundabout works (https://www.epermittest.com/drivers-education/roundabouts), I still can't understand how it works. Assuming 0 is the bottom and 90 is the right, how is it that a person following the inside route from 0 (exiting the left lane at 180) isn't going to get hit by someone following the outside route from 90 (exiting the right lane at 270)? I would almost certainly use it wrong and/or expect to get hit.