That’s one of the reasons why rein is so bad compared to tanks like sigma, orisa, ball, and hog - they nerfed healing and he takes too many resources to be able to brawl.
Why use tanks like rein winston, or d.va, especially with all the damage power creep and healing nerfs, when you can take tanks who require far less sustain to keep alive and allows your supports to do other things?
If you’re going to pour all those resources into them, than they better provide a lot of value.