Is it? Places with little forced mitigation like Brazil are still having waves. Some portion of the populace will be cautious and take precautions, and transient herd immunity within networks of people out and about will prevent some less cautious people from getting it during a given wave.

To truly burn it out in real world conditions you’d need to actively infect people.

Biochemist here. No it is not, and that's not epi-101. By letting it rip you're not just maximizing your fatalities, but you're also maximizing the rate at which the thing mutates, which maximizes the probability that your "recovered" pool becomes vulnerable again.

>but you're also maximizing the rate at which the thing mutates

No country is a closed system. We see now that a previous immune response is better than nothing against the Delta variant. I'm wondering what will happen to the island nations that kept the virus at bay while not having a high vaccination rate, won't they have many more deaths now with the more infectious and more deadly version that other countries that "let it rip" like Sweden have at least partial widespread immunity to?

True. But suppose you had no vaccines, then roughly the same mutations will play out whether the epidemic lasts a week or a year.

(Also, what the sibling wrote)

If you have healthy, low-risk people intentionally get the disease (from a single variant which you keep in good stock) and then strictly isolate/quarantine until they get better, that'd be a potential strategy. It's probably the best way to get overall immunity high enough that COVID would burn out... ...of course, this is basically the same as a super crappy vaccine. Vaccination would be way better. But back when people were poo-pooing the possibility of a fast vaccine development, it almost felt tempting to just do this and get it over with.

Because the virus wouldn't be spreading beyond the host that got it, the risk of mutation would be small.

(IMHO, we should've just massively accelerated vaccine development... even just a couple months would've saved lots of lives. If you're willing to try the strategy in my post, then accelerating vaccine approval would probably be no worse morally and probably a lot better.)