It is about intent, not size. Either/or.
I can put a little S70 Canon in my pocket. I cannot do that with any of these three. I can put much more easily, a tiny Exilim or iPhone, or Ixus in my pocket, but I’m only going to do that if I dont CARE about results.
The Canon is way too big, as is the RX10, to go in anyone’s pocket. It needs a bag, or to be on a strap round your neck.
So you might as well have a DSLR. Really. Even an a6000 or Fuji Xpro style APS-C is as big as a DSLR, and there are a lot smaller ones than a D7100 with a 24MP sensor.
The question is “Do you want to be able to take a photograph?”
With the 20MP RX10, you have what looks like a camera, it has a very good lens, but it is just NOT CAPABLE of taking a realistic photograph. It produces good graphics, but they dont compete with even an old R1’s photographs- they can’t. And you’ll be about £900 poorer. And Richard, your lens aperture thingy is way off. The smaller sensor’s shadows block up at base ISO with any f !
Started out doing photography at the age of 6 using an uncle's old 1940 kodak brownie box camera. At 15 years of age, I decided to buy my very own 1975 Praktica SLR camera. I now shoot with a Nikon D850. I do unpaid TFP and commercial paid work.