The jump from M365 to D365 is significant, as is the jump to Azure. One can reasonably use the productivity suite independent of the vast suite of cheaper (and often more suitable) services that can be used in place of D365, not to mention Azure.
I remember when my previous place was looking into Dynamics as an option for the company it seemed like it would be very much easier to deploy various Dynamics-adjacent bits to Azure, and we didn't want to be multi-cloud so this was a minor detractor for us.
M365 to Azure is a bit more of a jump maybe, but there's AAD which I think is a bit of an on-ramp? Then I gather Excel is getting better at integrating with the data products on Azure? I think there's something there, enough to make Azure the path of least resistance for some orgs.
