When I began in photography, back in the early 1950s, the Leicas I shot with were considered amateur cameras, perhaps suitable, in the most extreme conditions, for news photography, my profession as the time, but certainly not for anything "serious". After a couple of years in news work, for a (very) brief period, I attended the New York Institute of Photography, wherein a miniature camera was a 4x5 Speed Graphic. Absolutely no use for even 6x6, or, God forbid, 35mm. And, as wedded as I was to 35mm, a case could (and was) made for the tonal range of the larger formats. In those days nothing, absolutely nothing, could compare with an 8x10 contact print in terms of detail, resolution and dynamic range and, I dare say, that still holds true. All else aside, no small sensor camera will begin to compare to a large sensor camera in terms of detail, absolute resolution and dynamic range.
I personally prefer the smaller cameras for their speed and agility, but I do not delude myself that the overall image quality is a patch on the modern large sensor intruments.