My position is that Jeremy Crawford is obscure, D&D should not require sifting through Sage Advice to play, and if there is going to be an official redaction of the Monster Manual then it should be in the Monster Manual errata.You said it was still vague, citing older text in the MM. So is it your position that every errata and update is vague, because the original material is always still out there?
That's okay. Remember, AL is not a monolithic entity run entirely by rules lawyers. It's run by people who might be well versed on the rules (at best) but usually fall somewhere in the middle and make rulings based on their interpretations of the rules in the heat of the moment. Also, I asked him about casting magic weapon on your fists, not about Unarmed Strikes being weapons.Then no offense, but your AL is in violation of the AL rules. As an AL DM myself previously, that would surprise me that an AL DM would say that. The cardinal rule is that we have to follow the PHB and no other unofficial supplement or house rule.