From specs alone, the ART 20 seems to be a super version of ART9, not more, not less.
Yes, the generator appears to be similar. The use of Titanium in the body and a rubber compound for the under part of the cartridge seems to hark back to the construction of the ART-1 from around 1990. I still have my ART-1, but the cantilever broke off back in the 90's. I have mulled over getting it repaired as it was an interesting cartridge in terms of soundstage transparency - attached image is from the web:
