Neat writeup. I was always a fan of VMS; my university still had a VMS cluster that was used every quarter for class registration and completely ignored the rest of the year, but if you poked around you could still find relics of the old days, like ancient discussion forums software still containing posts from the 90s.
If I can put on my enormous pedant hat for a moment though, a VAX is a minicomputer, not a mainframe.
Well, to be extra pedantic, the latter MicroVAXen used the same enclosure as the "desktop" VAXstations, except without the graphics and peripherals -- just serial ports for a VT terminal!
We had that too in the early aughts--used a program called OASIS (may have been a custom application...not sure). Some older profs still used the VMS sys for email (I think it had PINE for VMS installed for easy use).
If I can put on my enormous pedant hat for a moment though, a VAX is a minicomputer, not a mainframe.