I can't lie I kinda forgot about punch 2 flying completely when I made this, haha. I knew firework flying was added after the elytra itself but I forgot people did that in its stead. The idea of this datapack is sort of as a response to people who think elytras are too OP and make other transportation methods useless. I'm personally a part of that same camp, but don't really think they should be removed or anything of the sort. It's a really fine balancing act that I'm not even sure this datapack is a solution to. The problem as I see it that elytras as they stand currently make exploration trivial, but removing them entirely would make building tall structures suck. In hindsight I think this datapack did the opposite of fix the problem, removing the utility that made it useful for building (being able to ascend quickly) while not really doing much to mitigate its exploration usage. I'm not really sure what the solution to that would be. One could argue the elytra itself isn't an issue as much as just a symptom of Minecraft's current progression. The elytra IS OP by design, it's meant to be an endgame item, but when Minecraft's early game can be basically skipped entirely and the endgame can be effectively reached within the first hour of a new world, one really wonders if the issue is the elytra as much as it is everything that surrounds it (and that's not to mention how much a lot of other transportation methods just really suck from a practical perspective compared to the elytra)

idk, just my two cents :p