We have 3 Surface PC's in our house (plus our Surface Duo and Duo 2 phones), so I'm clearly a fan of their systems, but I suspect Microsoft is misleading a bit with the data here. Surface buyers tend to be more hardcore into the MS ecosystem. Even among enterprise users, Surface is preferred primarily by companies with highly pro-MS IT teams. For the same reasons they buy Surface -- they are MS fans -- they tend to trust updates and be excited about deploying new MS tech sooner rather than later. These are also groups that moved from Slack to Teams and moved from on-premises domains to Azure AD before their contemporaries.
Therefore, I posit that what MS is citing as a causal relationship (that Surface systems lead to better OS adoption) is almost entirely just dual parallel symptoms of the same underlying root cause: interest in MS tech, both hardware and software. Dell and HP and Lenovo systems run Windows just as well.