There is no way to programmatically access Airtable’s record comments at this moment in time, but if your email is hosted with a popular email server like Google or Microsoft, you could very easily automate the process of creating a new record in Airtable for each new incoming email using Make.com. Then, you could link each email record to whatever project records that you would like.
And if your email is not hosted with a popular email server, you could always just auto-forward your incoming emails to a mailhook in Make.com, and then continue the process from there.