Fuji's approach is better for buyers. They have improved their cameras with firmware without having to buy the next greatest model.
Perhaps. Do you think that the price of those Fuji cameras has been set to include the cost of QA and development of updated firmware for older models?
Most, if not all camera makers, would rather have you buy a new camera to get those improvements.
And I would rather they gave me their latest experimental camera for free, but neither they nor I expect
those things to happen ;-)
In 2013 essentially the same chunk of additional functionality was provided for SLTA37, SLTA57 and SLTA99 in firmware updates; and more extensive firmware updates/bug fixes were provided for SLTA65 and SLTA77.
I don't know if that reflects a policy of only providing firmware updates for current camera models; or whether SLTA33, SLTA35, and SLTA55 were produced before Sony managed to modularize and standardize the SLT camera models.