Obviously buying a beater will have lower TCO, no offense but I don't see how that's really applicable.
I'll refer you to the table here:
https://teslamotorsclub.com/tmc/threads/model-x-comparison-and-total-cost-of-ownership.8498/ for a direct comparison of a Model X TCO and an XC90 TCO.
Ignore that persons colum called TCO. Just look at the "total" column next to it, which is the actual cost to own the car including payments, etc. I honestly can't tell what math is going on in the excel workbook but I assume they are smart enough to factor in loan interest the same across all vehicles, etc. As you can see, the "total" column for the model X is $112k over 5 years, and the XC90 is $120k.
So.... Are you really saving money here ?? Looks like no. Obviously, that table depends on his assumptions for repair costs, but as long as they are applied the same way across the whole spectrum, it doesn't really matter.