Actually, apple varieties are preserved via grafting. If you take an apple seed, the tree that will grow from it only has 50% of the DNA of the tree that made the apple. So there is absolutely no guarantee that the taste was preserved across generations.
Actually, even if you bred an apple tree with itself, due to the genetic recombination of recessive genes, the same thing happens. So it's more complicated than 50% of the genes missing.
Apple grafting is incredibly easy and cheap. All you need is a bit of knowledge, a utility knife, cheap flagging tape and ordinary waterproof wood glue. Planning to procure scions and watching for the bark slip is necessary - usually right around when buds start to break. My first graft was successful. Now I graft all the time. Peaches were a problem for me until I learned that they must be grafted after blossoms drop - usually later than ideal apple grafting time.