Any decent 3rd party client does this already. Take for example, thunderbird or k9-mail - major open source ones. Even Mail (from Apple, macOS) does this. What else you need? Sure if you use mutt or ALPINE read the related forums for help.
while anyone can criticise any large company one should do it for the correct reasons.
> This is anti-competitive behavior designed to make it as hard as possible to use email client software
Use App password. They are not blocking any 3rd party clients. Are you advocating using real password in every random client that may or may not transmit it in full text elsewhere?