New variants may not be a problem: Even if a new variant mutation occurs, it has to replicate lots and lots of times to get spread to anybody else. Few of those "replications" would be viable if the antiviral drug is still there.

What few people are talking about is that some of these "wonder drugs" may be so effective that the patient may not have enough virus for long enough to gain any immunity. Great for acute treatment, but not so great because the patient can get reinfected within a week after treatment ends. That avoids the "reinfection as booster" phenomenon.

I think the standard medical advice should be to quarantine for a couple weeks and then get vaccinated after an antiviral treatment.,

Educating anyone benefits everyone.