A similar topic to this came up in my town last year. A resident in one of the posh neighborhoods in town complained to their HOA that an unsightly work truck violated their HOA guidelines. Not necessarily that it was noisy, they just felt that it didn't fit into their neighborhood due to appearance. Even though it was parked in their driveway and not on the street. Caused a big to-do on the local NextDoor app and FB groups.
I'd talk to your neighbor. Is there somewhere else they could park? Honestly, before 7am isn't too bad IMO. If you'd have said before 6am I might have a different view.