Which is it? An engine rebuild is a significant cost and down time and he's not sure how many times it has been rebuilt? Makes me question the validity of the rest of the article's data when you don't know your own basic facts/history especially for is a major repair item.
This taxi driver must be a race car driver in disguise. Or this article is indeed questionable.
It does seem like this gentleman simply assigns some value to driving around in a Tesla all day, which is fine with me but the article should not try to make it seem economically rational.
However, if Tesla has worked the bugs out of their drive units, these cars would make some sense for use as cabs, especially if you're able to charge more than regular cabs: an EV should have much lower maintenance costs than a regular car, plus much lower fuel/energy costs (cabs are driven in the city all the time so they get lousy fuel economy compared to most regular cars). The main problem I see is Tesla's high maintenance charges (e.g., they'll probably charge you a lot more to change a wheel bearing at a Tesla service center than a Toyota dealership would for a Camry), however things like wheel bearings are things that an independent mechanic should be able to handle just fine, assuming they can get their hands on a compatible part and Tesla didn't use some odd-ball part. It'd be even cheaper if this cab driver can do his own repairs like that; wheel bearings are not that hard to change, though some of them require a hydraulic press, but you can get one of those at Harbor Freight for about $60. Others are simple bolt-in affairs that anyone can do with some simple hand tools in their garage.
The calipers are probably made by some supplier like Brembo anyway; it'd be nonsensical for Tesla to build their own. The trick is finding which brand/model they really are and what's compatible, like you said.
This taxi guy should start his own webpage about Tesla-compatible repair parts.
On a Subaru engine you basically have to pull the engine to do anything more than timing. People joke about having to pull the engine to do spark plugs but it's close to true. If the engine is already pulled nobody skips the opportunity to do plugs.