Again, there could be a difference, but we don't know yet. So until we get actual credible data, it is safe to assume that both these consoles have similar digital sales ratio.
Besides, in another one of these threads, I did some rough calculations to prove a point: even if Xbox had a very high digital sales ratio (compared to PS), it wouldn't have made a big difference in the end.
For example, PS is selling roughly 70% digital copies. It means out of 125 million PS users, 87.5 million players buy digital. Let's assume, Xbox has a whopping 90% digital sales ratio (impossible to have such a big difference, but let's assume that for now). That'd mean that out of 50 million Xbox players, 45 million players buy digital copies.
Even in that case, 67% of total digital sales would be on PlayStation, and only 33% total digital sales would b on Xbox. It'd still be almost 70/30 and 75/25 when combined physical + digital sales. Because of how big the PS userbase, a 10-20% difference in digital sales won't make a noticeable difference.
But again, we have 0 evidence that Xbox users buy 90% digital copies. As a matter of fact, whatever little evidence we have, points out that PlayStation users actually buy more digital copies, not Xbox players.
According to
Gameindustry.biz data (published on Feb 8, 2021):
That leaves 21% for Nintendo Switch and Xbox. Nintendo Switch has sold 2x the number of Xbox consoles. So, logically, Xbox should have 7% of the remaining total, while Nintendo should have 14%. So 52% (PS4) vs. 7% (Xbox). But let's divide 21% equally b/w Nintendo and Xbox, and we are left with 52% (PS4) and 10.5% for Xbox.