Microsoft will block Windows 10 users from installing the Windows 10 May 2019 Update on Surface Book 2 devices with NVIDIA discrete graphics processing unit (dGPU) Surface 2 users will not be offered the May 2019 Feature Update until the issue is resolved. Apple Macs with older versions of Apple Boot Camp or Windows Support Software drivers will also not be able to install Windows 10 version 1903. Microsoft is still blocking some Windows devices with compatibility issues from receiving the May 2020 Feature Update to prevent users of incompatible computers from experiencing degraded performance and issues after upgrading.
Source: https://www.bleepingcomputer.com/news/microsoft/windows-10-v1903-upgrade-blocked-on-some-surface-2-devices/