It's not happening, and it doesn't matter, because the hospital loads would be far more manageable. Vaccinated people are far less likely to catch it, and even if they do, are less likely to spread it, and are infectious for a far shorter time span. Look at infection maps or data on spread.
It's why I say we're not ready. If the conversation is not managed properly, it will come across as goal-post shifting. This happens less if expectations are managed. Right now, we're acting like the unvaccinated a threat to the vaccinated (or our kids), so if the flip happens it will be easy to misunderstand. Hospitalizations are going to become manageable regardless, because Delta will burn through, so it has to look like goalposts aren't shifting.
The cost of vaccinating people who have already had COVID is very low.
Much higher than you think, because it can be used to show that this is more about control than science. This, coupled with a denial that there's insufficient science, can make people look positively 'anti-science'. Democracies strive to have the consent of the governed, so we risk losing the trust of people we'd prefer to trust us. There's an entire cohort of people who will become 'safe enough' once they fight off Delta, such that forcing them to get a booster isn't worth the fight. You're correct that it risks creating a perverse incentive, which is why I say we're not handling the conversation very well.
As it is, I continue to have negative incentives to get tested. The best I can do on this front is point out that there's a negative incentive. It's like we have an entire of technocrats above us that don't know Thing One about behavioral economics.
Here's an example of someone not handling the conversation well.
that just provides an avenue for anti-vaxxers to cheat the system
There is no 'cheating' the system, we have one goal and that's to control case loads and reach herd immunity if we can. The vaccine provides massive personal benefit, so there's no pretending that someone who's vaccinated has taken some noble step that someone else refused to take. Vaccination makes sense from either a selfish or community level.
Now, maybe in your head they're cheating the system and you can think of a thousand reasons to do it for their own good. But we're not handling the conversation well.
As an aside, I've had pretty good success helping people deal with the lockdowns despite the weird social messaging right now. It comes across as if the vaccinated are 'afraid of' the unvaccinated, so we're locking down. At the individual level, I reframe it as "We cannot afford for you to catch Delta yet, the vaccine means we don't care if we spread it around amongst the vaxxed". It's tended to work, because once I show someone the odds of them being hospitalized, they realize that they should avoid the risk of needing to be hospitalized and re-emphasizes that it's a self-inflicted wound.
I don't emphasize the herd immunity aspect at all, because this has never swayed the remaining cohort (and they even pretend that the AZ cohort was 'scared of the virus' to each other). I just straight up say they're gonna catch Delta eventually, and we want hospital space for when they do. So, not right now, please. Then when they pull out the lack of a local McCullough Protocol, I can dryly say "It needs an RCT, but if it works it sounds like it's nearly as effective as the vaccine".
