Toyota moves at glacier speed (say glacier speed from 1900, not 2016...) in terms of model changes. Even when they change platforms, they're likely to keep existing drivelines if they're working well. Change for the sake of it isn't their thing. For some consumers, this is awesome, and for some, they don't like it at all.
Then there's a massive "middle ground" that don't really know and don't care. They look at the exterior, the interior, and go for a drive. Even in the expensive segments, this is true. If you drive an IS350 or GS350 you just know the engine pulls amazingly well - I doubt many buyers care about when the engine went into production.
There is an underlying strategy here. By keeping proven tech even into new models, it keep failure rates low and CR ratings high. This is the backbone of Toyota's sales strategy - rock solid cars that last, last, last and retain resale.
