As you mention, MTG represents all of Hasbro's profits. I don't feel that there is a way for them to escape the allure of watering down the MTG market in pursuit of more money. I feel they will kill the golden goose. At some point the physical printing process has to become a liability, right?
I don't know what percent of MTG newcomers play paper-only. Perhaps it is a lot, but my gut says that MTGA is the on-ramp for newcomers. With the digital cards not being able to be traded - newcomers aren't building the expectations that your tool is appealing to. Your tool is more useful to those who are already entrenched in the physical game space.
A counterpoint to what I'm saying is that Flesh & Blood has been doing well enough and Disney just entered into the space with their own, paper only, card game. So perhaps I'm wildly off base and the physical market is experiencing a resurgence?