Not looking to argue about this, but I just wanted to note a couple things on the topic. I'm just not sure why you seem to dislike mystic adepts not gaining access to astral projection so much. Firstly, it isn't like they are being excluded from something most others get. Only Full Magicians have the ability to Astrally Project. With 5th Edition removing most of the limits that are on Mystic Adepts, it is actually now the only thing that sets Magicians apart. This is likely why you've probably been seeing a lot of strong opinions against giving them access to it. Letting Mystic Adepts project, effectively makes the normal Magician a "less powerful Mystic Adept." Which isn't the point of the Mystic Adept.
You also seem to keep arguing that they "removed" astral projection from Mystic Adepts as a balancing tool, which just isn't true. They never had the ability to astrally project. From an in setting perspective, Mystic Adepts have become more common through some of the edition changes (which in turn caused a variety of setting growths and evolutions). They started out as an off-shoot of Adept, ones who learned to channel their magic in a way similar to how Magicians do. Adepts could always learn how to Astrally Perceive, just like Mystic Adepts still can (they don't get it for free, it still costs them a power point). So removing that would have been a "nerf" to what they had. Free access to astral projection has always been the magician's domain, and just because Mystic Adepts are approaching closer in power to the Magician, doesn't mean that they should have easy access to all of their toys.