Of course not, but unlike chat services, everyone has an email address or phone number, so if I need to reach out to them for something other than a casual chat, e.g. an invitation, a birthday felicitation, or a document that they should review later, email is a method through which I can reach all of them.

Similarly, reaching out to companies for support also often happens over email.

and also recovery keys, or login + password in a message from various forums.

Or payment receipts, either 2FA, or archives, documents)