The most popular MF sensor at the moment, the 50MP, 44x33 mm Sony CMOS sensor is roughly 70% larger than a 35mm sensor. It has a pixel pitch of 5.3 micron. A 24MP Nikon has a pixel pitch of 5.9 micron, a D810 4.88. The fastest lens made for the MF sensor is f/2, and there's usually only one of those for each system. For 35mm, there's an abundance of f/1.4 and faster lenses that offer shallower DOF and better light gathering despite the smaller 35mm sensors. Are the lenses for 35mm as good as medium format lenses? Some of them, like the Otus lenses from Zeiss, probably are. Even the 100MP, 53x40 mm Sony sensor is only 145% larger than a 35mm sensor, and now we are down to 4.6 micron pixels, smaller than with the D810 and barely larger than the new D850 (4.35).
10x8 is 58 times the size of 35mm. Yes, I believe you when you say that the difference in look is more obvious. 10x8 is also 17 times the size of the 100MP Sony sensor. A 10x8 sensor with the same pixel density as the 100MP Sony would be 1.7GP.
I like medium format, and I wouldn't mind shooting digital MF, but the only relevant future use I can see is for applications where very high resolution is needed. That won't stop photographers from buying it, and if I had the money to waste, I would probably do that too. But if I want to stand out from the crowd, I'll shoot medium format film.
Except for very large prints, only photographers and a few art directors see any significant difference between images from 35mm cameras with 36-50MP sensors and those from the current crop of digital MF. In the future, the difference will decrease further, since the technological progress will be more visible with smaller sensors. But the difference between film and digital will continue to increase, and the more it increases, the more attractive film will look. Not because it's better, but because it's different. And you can still get it in 10x8 you know