The problem is, DMs may wish to control which spells exist in the campaign world. By the rules, a wizard need never have seen nor heard of a spell to acquire it. As long as it's in the PHB, the wizard can get it.
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While I agree that eliminating the "2 free spells per level" is unfair, I think it reasonable to disallow "ANY 2 spells per level" and limit it to spells that the PC has encountered in some fashion or has invested time and money to invent. By the same token, players should give the DM leeway to limit cleric/druid spells to only those known by the character's order or mentor.