You're really saying no one should use concentration spells if they're frail. It goes down if they go down. And if they get surrounded, they're gonna get hit, and if they're at low health they'll get downed, and so will their spell. You do realize that they can have a concentration spell up and then get to low hp, right? Because it doesn't seem like you're grasping that It's not objectively better. You'll just make them lose their abilities that they've used if you let them drop. Being at 1 and at max definitely effects how someone plays. At 1hp, they won't be getting into the fray. Assume a fighter, at 1hp they're going to run out of the battle and cause the enemies to attack the others. At max, they stay in melee, and they draw hits. Saying that health doesn't effect how effective a player is, is objectively wrong. We play entirely different at low HP than we do at high HP.