Obviously with being two different games, from two different release dates, in different contexts, it's hard to make a good comparison and obtain real data from it, but still it seems the intention behind the tweet is obvious: Quest game sales are increasing, and at a good pace. And I doubt that suddenly they are selling half of the units for the PCVR version, it's just that the Quest version are selling twice as better, that's why the % is bigger for Quest and smaller for PCVR.
This and the news of Boneworks selling very well in only 3 days of release is promising for VR.