There are some RFC822 conform email-adresses that are incorrectly validated by @Email.
E.g.:

• Abc@def@example.com
• Fred\ Bloggs@example.com
• Joe.\\\Blow@example.com

https://haacked.com/archive/2007/08/21/i-knew-how-to-validate-an-email-address-until-i.aspx/ - 14.02.2020

I´ve provided a simple test-case: https://github.com/AlexanderGuril/javax-validation-constraints-email-not-rfc