The m4/3 made sense when I started with it, but not anymore, since there are excellent APS-C cameras that are physically smaller. For example, the Sony A6400.
I have to dispute once again that the dominant motivation for using a smaller format system is smaller
bodies—it is not as if choices between cameras in the same format are dominated by preferring the smallest body! With EVF cameras, there is a lower limit on good body size dictated by the ergonomics of controls, grip, rear screen and such that a particular user wants, not sensor size (which I will note is far smaller than the LCD right behind it, even in 35mm format.)
As far as size goes, what is far more important for many of us (telephoto users in particular) is the lenses, and things like having the smallest total kit that gets the job done for us. That is where smaller formats continue to offer an advantage.
But apart from generalities, the choice between MFT, Sony E, Fujifilm X, Canon M, etc. often comes down to the specifics of how well the system is supported by lenses that go well with the bodies, typically needing a good array of lenses designed for that format and lens mount, rather than lenses designed for a larger format or different lens mount, so requiring a heavy crop of the FOV they were designed for and/or a mount adaptor. There, I would say that MFT and Fujifilm X make a strong case with respect to the other "APS-C" format EVF camera systems, whose makers now seem chronically distracted by 35mm format.
But maybe that lens system issue is not important to Marc, given this comment:
All those lenses were taking the fun out of photography for me, and I found I was leaving the Olympus at home. Just acquired a fixed-lens Fuji X100F.
I agree than for many, a fixed-lens camera in 1", 4/3: or APS-C format can be the better choice, at least for a lightweight kit. But a singe focal length camera like the X100F is the absolute opposite of what I am looking for!