I generally trust the major cloud providers a bit more than the companies focused on acting as a domain registrar.
The domain registrars are generally a race to the bottom and focused on "add-on" sales as most people are shopping on price and that's going to reflect in the overall quality of the things that most people don't really notice like, y'know, security and validation.
You don't hear a lot of stories about Amazon/GCP/Azure handing over someone's entire account based on a couple digits of a credit card number and it would be a PR nightmare if they did (hell, look at the flak they catch just for the data that people leave public on their services that ends up released... imagine if they handed it to someone). An active account with 2FA/etc enabled and a secure recovery email is probably safe enough for most people.
Spend the extra couple bucks to register through one of those guys instead of JimbosDiscountDomains.
Or… use a smaller registrar which actually charges more in order to provide support which you can contact personally. Most (if not all) large registrars are indeed in a “race to the bottom”, but that does not mean that all registrars are.
(Disclaimer: I work at such a small registrar. No, I’m not going to tell you which one; we aren’t targeting the global market, anyway, only our local area.)
The main issue raised several comments up is portability. No provider locks you to only using their email offering/cloud offerings if you register their domain through them. Even if they did, transferring domains is trivial and well-supported everywhere.
As far as any other objections people usually raise around using hosted email and the like, a domain really has no comparable privacy implications in the real world (you're not handing Google or Microsoft a huge corpus on your life). It's also through their enterprise offerings where as long as your bill is paid they're generally not going to have some automated review suspend your account with no reason, and if they did they have actual support you can get in touch with.
This solves basically all of the problems with using an @gmail.com/@outlook.com/etc email address.
Google, Microsoft and AWS offer registrar services becuase it keeps you in their ecosystem for their higher margin products. THey generally offer competitive pricing for things like doamin registration and don't pull stunts like charging 2x as much for "privacy protection" or the even more dirty tricks like godaddy and other bottom feeders.
I recently trialed hosted email with AWS and while it is very basic it only costs 4/user/month - cheaper than my google apps service. I was also able to register a new domain at market rates and get dns automatically setup (I think?) on AWS as part of the service. Now because I tie my monthly AWS spend with my registrar I'm more confident I can get some customer service as well.
staying inside a vendor's ecosystem for very selective services can actually work out quite well, as long as the seller/customer incentives align and they are relatively commodity services.
The domain registrars are generally a race to the bottom and focused on "add-on" sales as most people are shopping on price and that's going to reflect in the overall quality of the things that most people don't really notice like, y'know, security and validation.
You don't hear a lot of stories about Amazon/GCP/Azure handing over someone's entire account based on a couple digits of a credit card number and it would be a PR nightmare if they did (hell, look at the flak they catch just for the data that people leave public on their services that ends up released... imagine if they handed it to someone). An active account with 2FA/etc enabled and a secure recovery email is probably safe enough for most people.
Spend the extra couple bucks to register through one of those guys instead of JimbosDiscountDomains.