What's likely to be cheaper is long-term repair costs. No muffler replacements, no leaking head gaskets, no timing belts making an attempt at freedom.... But whether that actually works out remains to be seen.
When he took the Model S in they added that metal plate to the bottom (from that one crash that got a lot of press), swapped out all the door handles for new ones because people online complained that in rain sometimes the old ones wouldn't retreat into the car and changed a few other things I'm forgetting (at no cost).
I can't really think of another car company that proactively adds a bunch of stuff to the car for free as a part of routine maintenance. Of course this is in addition to all of the over the air software updates too.
Adding backup lines to the backup display, on the other hand, to 2 year old cars, that was unusual. It was purely a software upgrade.
FWIW I've only ever changed the oil on my 2006 Ford Focus.
You better change at least the timing belt, transmission oil and sparks plugs if you hope it to keep running well into the future.