All the companies do... They call it lifecycle of the product.
I will keep my fenix5x until it dies then i will buy a sunto or a polar watch!
Of course we won't see any new features on fenix-5x. For example take a look at the beta firmwares that they release in the last period. They did not place not even one single new feature. They want us to buy their new more expensive watches and only then we will have those new features. Like always, garmin does not care what clients wish, they only care about the money they will get from us. More money they get, then more happy they are.