> re: your edits, the tangential bit from this paper about sars-cov-2 positive cases wasn't the main thrust and from the graphs it looks like their neutralizing antibody levels actually are multiple logs below mRNA vaccinated people at the same 15 week point. I'm not sure what all these citations about naturally infected people add to the topic being debated.

These are all real-world studies of actual duration of immunity. They trump any theoretical concerns based on lab measurements of neutralizing antibody levels.

Observing that the vaccines induce responses lasting as long as 15 weeks is completely unsurprising, based on what we already know from real-world observation of natural infection. Ignoring contextual evidence and concluding that this specific paper didn't provide reasonable evidence is losing the forest for the trees.

Could it be possible that the vaccines don't confer immunity lasting as long as what we're observing from natural infection? Sure, I guess.

Is it likely? No.