Nice graph! The line shows about 10 doublings in 12 years so that's one doubling every 14 months (maybe it's just a bitslow because DWave seems to have had only 1 doubling in the last 2-3 years).I haven't heard of the Moore's Law for qubits, apart from this (I'm reading it's sometimes called Rose's Law):
I strongly believe in Japanese technological culture and though. Since their RIKEN, unis and firms have already been on it for a decade or so, I'd expect some fast progress in processor capacity within the next 10 years. The fact that it's currently attracting a huge funding in the US can help too - but I'll stick to my Nipponophilia
I'd assume that quantum computing performance is exponential in bit count (correct?) so that if bit-count is exponential in time, then performance is double-exponential in time. (But is that also true of quantum annealing systems?).