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...
And what you're going to find too is that as the sub price goes up, the users who use it the least (generating less API costs) get priced out first. In other words, the average cost per user increases because the users who are willing to pay more are the ones who are generating more costs. If 75% of users stop using it because of the subscription cost, the API costs won't fall by anywhere close to 75%.