Yes, absolutely true and not in dispute. However, the only legitimate reason for a company to want your email address is to communicate with you regarding the product - check, that issue is resolved. The only reason they would need your real email address is if they planned to do something with that address other than communicate, like sell it - that's the point of Sign in with Apple.
The post I was responding to originally stated that company's would not be happy not getting "real" email addresses and that is what I was replying to.