I'm starting a new campaign playing as a raven queen warlock, and my DM is hesitant about Agonizing blast (adding charisma damage on hit for eldritch blast). He argues that it since at high levels, a warlock with EB AB will be doing 4 x (1d10 5) damage, and a vanilla fighter archer will be doing 4 x (1d8 5) damage, AB makes archers superfluous and has the potential to ruin the fun of someone who wants to play as an arher.

Every post I can find Jeremy crawford has confirmed that this is the way it works, but I also see his point: competitve, infinite sustain damage should be for martial classes and not for classes with access to 9th level spells.

IMO some of the difference can be accounted for by the following: extra crit chance for fighters, colossus slayer for rangers, the chance for magic weapons and the benifits of being dexterity based.

So I'm seeking some opinions: does anyone else feel like warlocks with AB take away from the fantasy of being an archer? Are there other ways that archers make up the difference with ways I'm not seeing? Are martial classes just underpowered?