At the end of the game cantrips are not so useful anymore (Level 10 +). If quicken spell only allows you to cast one addinoal cantrip to make f. e. 5 HP damage for a 400 HP foe this feat is not so useful compared to what fighters can do in this game.
This is incorrect. Cantrips level with you. At 5th they deal 2 damage die, at 11 it’s 3, and at 17 it’s 4. It is the same average damage as 4 sword attacks minus ability mod damage.
