sp_send_dbmail usage best practice I would like to get some clarity on the usage best practices of sp_send_dbmail and I cannot find any answers online.

Our developers love to use sp_send_dbmail to send out application related emails from within the application. Say for instance a user forgets their password, they will send the password reset email that a user requests by executing sp_send_dbmail. This is just one of the many types of emails they send using this stored procedure. Is this a good practice? To me it feels like a dirty solution as there are many API's out there that can handle email sending in your application and as a DBA, I don't like enabling these options on the production servers. I just don't have a choice. Maybe with enough motivation and proof that it's bad practice and/or potentially dangerous for various reasons I can sway them to change it.
SQL Server core licenses are expensive: using a SQL Server machine's CPU to send thousands of emails has no justification, especially when there are countless better options in terms of features, manageability, setup, troubleshooting.

Another point is that tight coupling between the email and database features makes the application difficult to scale, isolate and manage. One server - one service.

Database mail, in my opinion, should be used for administrative purposes only (alerting) and not for sendind business email messages.