I'm still convinced these benefits
are mostly illusory. Suppose a Mystic class is released in 2026. Under a class-based spell system, a player who wants to know what spells their Mystic can learn will need to check the list published with the Mystic class, and then the lists of spells in any post-2026 sourcebooks. Under the Arcane/Divine/Primal system, the player will have to check for spells of the appropriate source/school combinations in
every sourcebook. The Arcane/Divine/Primal system may clean up the spell lists aesthetically, but in terms of the actual player experience, the complexity is a consequence of having spells and classes in multiple sourcebooks, not of using a class-based system.