For personal or family, I think Fastmail is fine. I use it for a family account (paid years in advance), and admin other Fastmail tenants "family office" style for those who trust me to and offload the responsibility. I can get ahold of someone at Fastmail easily when issues crop up, which is rare. O365 is what I recommend for anything SMB and up. You can at least get support from Microsoft when needed. AWS is fine for cloud resources and infra, again, you can get support from a TAM or similar. But Google? I have never once had a good experience attempting to get in touch with a human when resolution is needed, hence my position on the topic. You cannot self serve critical business infra (imho), and Google is allergic to providing human support.