I disagree. I can think of a number of companies/business types where a common email for communications with clients is required. Think of any company with a reception that arranges appointments. Would you expect the client to receive emails from every receptionists specific address (even though there could be more than half a dozen)? If all correspondence comes from a common email address, the client's email client would be more likely to group the conversations (even if a basic email client that sorts by sender).

If you have set up your Odoo properly and you are following the Odoo workflows, this will not happen. There will be a communication thread about an appointment and all communications going back and forth are collected in this thread under one email alias. This works fine, is intuitive and convenient for the communication partner. Personal email aliases are only used when you send personal emails which are not related to documents or workflows and in this case this is for sure necessary in order to keep the threads intact.

But it is important to see and know how it works before taking decisions.