To each their own, but I find this decision really misguided.
It's her money, not mine, so whatever, but l do not expect her to turn a profit in, rather the opposite.
In my view, the cross section of "IfR" users and people willing to subscribe monthly is rather small (especially if the money mostly goes to reddit - assuming I could afford it, I, for instance, would rather fund an open system like Lemmy).
And if Apollo's dev Christian Selig decided that it wasn't worth it with an already established paying user base, who already has a strong culture of subscriptions and exaggerated pricings, and one of the highest volume of users, at what probably was the peak usage of the platform; I don't see how a small app like IfR can survive.
That, or he made a pretty expensive mistake...
App developers have already agreed to some Reddit ToS in order to get an API key, so one of Reddit's powers is to sue them. Developers don't want to risk that, so they just follow the agreement and whatever Reddit tells them.
Individual users would still need to request becoming a developer, a process which Reddit has recently changed, and agree to the same ToS to get an API key, but the risk of getting sued instead of just banned, would be much lower. The ban could include both the API key, and any users using it, so still risky other than for throwaway accounts.
Reusing the official app's API key though, could be interesting. Still risk getting banned, but interesting.