Magic *is* difficult to procure from the treasure tables. I made this change because I have level 4 magic users at my tables who still only have their original spells. Its frustrating and unfun for them as this is their only way to actually progress their characters.
Magic users level up the slowest, they have the harshest gear limitations, and the few spells they do get are completely random.
Any changes I make is not without layers of playtesting and player feedback.