Apple policies do not really benefit anyone. Kindle iOS users will simply open Safari to buy their books, making their experience worse.
Either Apple should really remain objective and not have horses in the App Store race, or follow the same rules on its own apps that they impose on others, or change the rules to benefit everyone (including the users).
If your use case for a tablet is to read books or comics (which I suspect it is for many people! A lot!), then the iPad is terrible because of this specific limitation, and Android tablets are much easier to use. Shame Google seems hellbent on destroying them - the Pixel C really was a very, very nice comic reading tablet when it wasn't suffering hardware failures.