The same goes for eschew material components then. The chance of getting busted with spell components is way higher than being caught with your spellbook, which is likely stashed away carefully. Yet no one banned that feat.
I feel that Sorcerer and Psion are rather different. Both use abilities spontaneously, but the Sorcerer is far more constrained. Anyway - no Sorcerer = no Beguiler, no Dread Necromancer, no Warmage and so on. I can’t see any reason to exclude them. The starting point should be inclusion. Keep in mind that none of these classes, including Sorcerer, had any precedent in the Forgotten Realms either. Yet there they are.