Boosters have always had 15 cards (well, most of them, anyway) because that's what Richard Garfield chose to do with Alpha , years before designing for Draft was even a thing
Depending on how degenerate you want to be this can range from fun value to bonkers
That is a key point to note, do not assume just because a card is powerful in RDW that it is also good in Izzet tempo, a lot of them are but certainly not all of them
On the other end of things, original games such as Flesh and Blood have earned respect among hardcore trading card game enthusiasts looking for an alternative to Magic: The Gathering, but dont necessarily have the familiar characters and welcoming gameplay simplicity needed to bring in brand new players to the world of TCGs
It is a useful neutral baseline when both cards are matched by variant, language, and condition