Yeah, I didn’t understand what he meant either.
One reason why people might not think the accent is “Asian” (I think it sounds specifically Japanese) is because they may be judging the accent based on Japanese people who speak fairly fluent English. The accent, specifically the inflections and rhythm pretty much sound exactly like a middle aged Japanese guy who doesn’t speak English trying to speak English (it happens often in Japan).
Most Japanese in the media will have worked on their pronounciations and fluency, but everyday people obviously don’t.
I don’t even think it sounds like that fake Engrish crap I see people make fun of. It’s actually a fairly accurate “impersonation” (I don’t think this was Lucas’s intent).