i have one as well,
the surface 4 wintab driver that we usually install doesn't have tilt support.
On photoshop it uses the windows ink driver, "tabletPc"

+1
I have a samsung notebook 9 pro, and support for tabletPC driver would be good.
I can get pressure sensitivity with wintab driver but no tilt.
On clip studio tilt also only works with tabletPC, so maybe is something wrong with wintab