Using Azure Files as a granular file share looks good on the surface, but it's not really designed to be a SMB share/Windows Server File Services drop-in replacement. I've used it as a drop-in replacement and found its limitations real quick.
If you have less than about 4TB, you'd be better off looking at SharePoint for commonly shared files, and OneDrive for Business for personal files. Not saying Azure Files can't do it with AAD permissions, it absolutely can, it just doesn't feel like it's quite there yet so you may have some struggles and finding yourself asking "why would they do it this way?"
I keep telling myself it'll get better and it will get there, but honestly it might not for one specific reason. Doing file shares the old way of SMB or CIFS shares is something Microsoft is still developing of course, but there are just better ways to share content (outside of SharePoint and OneDrive even) within Azure. NetApp has an Azure solution which is great, albeit more expensive than some simple Windows SMB shares.
Having said all that, I will say granular permissions in Azure Files for AAD accounts has gotten a little better since Azure Files' inception. Keep in mind Azure Files is still quite new, in case you feel like it's not ultra matured for end users.