The 4l60 in that Tahoe is on borrowed time. That's on the same order of cost magnitude as a battery.
For people who have to pay other people to do maintenance (i.e. most people) whether or not you buy a POS that eats suspension wear items for breakfast and how anal you are about getting every little scratch fixed will dominate long term cost. A couple grand for a battery or transmission spread out over more than a decade really isn't that much. Shelling out a grand every time your vehicle gets humped by a shopping cart will add up quick.
You can get a new tesla battery for 1400 ? granted most folks cant replace one but I can. I cant work on or replace a tesla battery. I have also rebuilt transmissions and that gets you a fraction of the cost because the clutch packs are typically the only wear out part... that and seals.
Look at Prius batteries. You can get cells for $25 a pop and rebuilt batteries for a grand.
Tesla will probably never reach that price point because they're a bigger battery and more on the luxury end of things (indeed a reman engine for a German car will hit your wallet harder than a crate SBC) but there's no reason to believe that the industry will all be hard/expensive to service like Tesla and other luxury brands. Also Tesla is particularly terrible about parts supply chain and locking everything down so you'll probably never see aftermarket batteries apply downward price pressure there.
Your Tahoe may as well be a Prius for the purposes of major component cost. Its major components are about the cheapest there are since it's basically a GM truck. It doesn't get any cheaper than that. The Prius is a valid comparison.
When a proper cheap mass market EV comes along it will likely have similar maintenance costs as a comparable ICE vehicles.
I see usually 4 figures over and the standard saying goes it takes 5 years to see the cost equalized. Owning a diesel will save you money but buying or leasing wont.
260k miles and it still goes strong, diesels easily get to 500k miles
An interesting twist would be using a hydrogen fuel in an ICE.