Comment by dotancohen

I don't know if this is applicable to hybrids, but taxis attain high mileage with relatively few engine cold starts. Engine cold starts are what kills main and conrod bearings and piston walls. Taxis' bodies may be beat to garbage, the interior might be trash, but the engine and likely the transmission too will be representative of a vehicle with an order of magnitude less kilometers driven. Because they go an order of magnitude further between cold engine starts.

All this assumes proper maintenance, especially oil changes.