> How do you assuredly get R0 below one with a leaky vaccine[1]?
Nobody was assuring anything. It won't get it below R0 by itself, parent comment already told you. It's the combination of seatbelt, airbag, while not speeding, drinking, smoking or talking on the phone what keeps people relatively safe on the road, not any single of those elements.
> R0 can stay >1 with 100% vaccination if the pathogen is contagious enough and the vaccine is leaky enough.
Yes. That's why the epidemiological consensus is for vaccinated people to keep wearing masks, particularly indoors.
> There is a very real chance that we're going to look back on delta fondly if a Marek's disease type scenario unfolds
Excuse me from what I'm going to say, but the Marek comparison is an antivax favourite from the gross misunderstanding that you seem to share with them.
The Marek scenario is the result of imperfect vaccination, plus the massification of the poultry industry, plus the fact that infected chickens can carry and transmit the disease for life, including those vaccinated, which is absolutely not the case with COVID-19.
The disease existed before, but outbreaks were relatively local and self contained.
Now, from the second half of the 20th century it started being a major concern with the industrialization of farming. With a vaccine that keeps chickens from having complications or dying, but not from shedding virions for life, all while living on top of each other 100% of their lives, sure, you reach enough selection pressure to make the disease evolve for the worse.
COVID-19 vaccines may let you be contagious for a few days, then the infection eventually clears, and the density of our dwellings is orders of magnitude lower.
> Then again that's pretty much optimal for big pharma if they have a vaccine that's effective against a hypothetical omega strain that will reliably kill or maim the unvaccinated.
Yeah, this goes deeper into tinfoil hat territory. I'd just like to say that interestingly most of big pharma failed to produce vaccines and have been there largely to give the manufacturing power to the small research groups and small/new biotech companies that actually created them.
Luckily there are dozens of vaccines from all around the world by now, I think competition will do the rest.