I am running my own mail server for 3 years now. There were some issues (outlook pushing emails to spam folder) and an IP change (not sure how that affected things but I resubmitted the IP to the Microsoft email tools, can't remember the name of the service).
I would like to join some movement or a class-action lawsuit against big tech for anti-competitive practices regarding private mail servers if such thing exist, and if not i would suggest we make one.
Not that exciting tbh. You showed nothing new and it's probably going to be paid software (closed source for sure), and comparing that to VSCode + Copilot (which is blowing my mind day by day) I don't see why would I switch. And that pair programming session is so faaaaaake.