It’s a natural part of the role. Has been… forever.
If a car company released a car in America with right hand drive, that would be stupid. You won’t have to. There’s no law against it. But it would be stupid. People wouldn’t like it. And the car wouldn’t sell.
The dispel situation (and defensive situation) are similar. Keeping people alive = healer job. They can keep designing dungeons that spread the responsibility around, but people aren’t going to like it and they’re going to stop playing before they change their expectations because someone “said so. “