However, even though I'm fully vaccinated and boosted so personally have no reason to fear COVID from the point of view of landing in the hospital or dying directly from COVID (and all my friends and family are in a similar position) it is still an indirect concern because the unvaccinated are taking up hospital resources that I might need.
Even in my county in the US, which has been in the bottom quarter for case, death, and hospitalization rates in my state, which has been in the bottom 5-10 states for all of those statistics for the entire pandemic, there are enough unvaccinated people in the hospital now with COVID that hospitals are almost unable to take new patients. Omicron looks like it is peaking here, so it will probably be OK to go ahead and have my heart attack or get hit by a drunk driver without worrying about whether I'll be able to get treatment, but there are a heck of a lot of places in the US right now where this is not the case.
The good news is that after omicron, enough of the unvaccinated will have some immunity via omicron that it should bring their hospitalization rates down enough that it is no longer a problem. That's when we reach the "it can be treated like a a cold or flu from a public health perspective" stage. A recent NTY covid briefing email looked at the data from places that are ahead of the US on the omicron curve, and that's what they concluded.
The solution to this is to bump the unvaccinated to the lowest priority of hospitals. If beds are full they should be removed from the hospital.
The effect is that these decisions result in a small increase in the steady state hospitalization levels. If obesity or smoking increases the effects of that increase on hospitalization will be spread out over decades giving plenty of time for hospital capacity to be adjusted to deal with it. (Same if obesity or smoking decreases--hospitals won't suddenly be laying off staff. Hospitalizations would fall over several years giving hospitals plenty of time to reduce capacity by simply not replacing as many workers who retire or change professions).
COVID-19 is bad for hospitals because it is short term. That's why in the US we are currently getting about 20x as many daily COVID-19 hospital admissions as we got cancer admissions before COVID-19 (that's for all cancers, not just lung cancer).
I’ve learned of many cancer diagnoses in my circle of family and friends and can think of only two that had a hospital admission related to it (most were treated as outpatient procedures, including most of the surgeries).
So no, even if those ethical questions would be resolved in favor of it, it is at best a solution during a future pandemic. It is not one for this pandemic.
Imo the only thing that really matters is the hospitalization rate of the vaccinated. If it's near bad flu numbers, then there's no more concern