So the message that seems to be coming across to me is that really medium format is just for someone that wants a toy to play with. I might as well really forget the expense of doing it and go back to my digital unless I want a new toy. I always got the impression from listening to so many photographers over the past couple of years that there was someone advantage, but obviously not.
That isn't what I was trying to convey.
I really enjoy using medium format film. When compared to 35mm, it gives me negatives that are frequently nicer to print in the darkroom, and easier to scan effectively as well. The viewing systems in my various medium format choices are very nice to use, and I've got all sorts of useful and fun to use accessories for my medium format cameras - some of which are brilliant. And I particularly enjoy the 4/3 aspect ratio of my Mamiya 645 Pro.
When I'm printing something for exhibition purposes, I'm more likely to be satisfied with the results from medium format negatives than from 35mm negatives, but that doesn't mean that In don't have exhibition prints from 35mm that I am very happy from.
And medium format transparencies look really wonderful when projected!
But that wasn't what I understood you were asking about when you started this thread. I understood you to be asking about what sort of photography or what sort of subjects it was that medium format was particularly suited for. And the answer is that outside of some special subjects, medium format isn't best for anything in particular, it is just really good for all sorts of things. It really isn't any better in any special way for subjects like machinery or people doing manual labour than 35mm or large format is - its advantages and detriments are the same for those subjects as just about any other subject.
The same applies to the 6x4.5 format, other than the fact that the portability and handhold-ability of the 6x4.5 systems sometimes makes them practical in situations where one might have assumed that something smaller like 35mm would have been required.
There is a really good chance you will find it very enjoyable to uses your Bronica. The camera is really well designed for that. If so, that is what will lead to great results, more than anything about the cameras capabilities and technical features.
Here is some 6x4.5 based "machinery" - because you asked

. In this case, handheld and employing my rarely used waist level finder.