Most of those platforms seem to require the patient to pay for a virtual visit for every refill, or require some kind of a monthly fee.

That is accurate. But those virtual visits are 50% cheaper than full telemedicine visits and 70% cheaper than in-person renews.

It should be noted their virtual visits are mostly performative. You're filling in a survey beforehand and the doctor is just there to read the survey and push a big green button.

How long do the refills last? I would think that even with the cheaper cost of medicine, and the discounted telemedicine visit, it would still be more expensive than seeing a doctor annually and getting refills for all prescriptions for the rest of the year without needing additional appointments. But perhaps I'm underestimating how cheap these platforms are (both the meds and the docs)?

They aren't that cheap. But when your doctors appointment is $120+/each, they don't need to be that cheap, just cheaper. They're like 20% cheaper all-in compared to the traditional way, and you don't need to leave the house.

Plus many of these places specialize in stigmatized products like anti-bolding, ED meds, anti-depressants, etc.