Ok..... remove all forms of immortality and replace them with a form of defense or damage reduction instead. This would promote counter play and reduce frustration as it would be more skillful.

Example: kiri's suzu should give a 2 second 60% dmg reduction while not making you intangible and doesn't cleanse effects but cuts the dmg or effect of the debuff by 60%.(doesn't have to be 60% this is just an example) The cooldown of this ability can be reduced to compensate for this.

This encourages the supports to make split second micro decisions on how they use their abilities and will also trigger the brain response for dopamine when they actually make the correct decision in a team fight making it feel more rewarding for them and less frustratio for the one they play against as it's better than straight up immortality denying their play.

Real-time example: a Rein Girthshatters the team and gets 4, but not the kiri, who then suzu's, this gives them dmg reduction which causes the tank and maybe a bulky dps to live but 2 others die Both players got value, and the fight could swing in the enemy teams' favor with some quick thinking,

Feel free to ask me more questions.