Incomplete assumption. Greatly increased infectiousness, shedding, and higher viral loads upon infection screw that all up. Then that is exacerbated by a large % of the population unvaccinated and basically not taking any precautions at all. Even many of the vaccinated have been mal-informed by gov't and media or are loaded with misconceptions and / or misinformation about what vaccines for respiratory viruses can do: Result is another big swath of people blithely risking repeated exposures to high viral loads.
Given the above I am frankly impressed the vaccines are reducing serious and fatal cases as much as they have. Be under no illusions: Without the vaccines, and with behaviors the same as what we have now, we'd likely be running several thousand fatalities a day - maybe since Delta got seriously going.
Can you imagine the squalling if the COVID vaccines were as effective as an average year's flu vaccine in reducing CFR?
It may be an incomplete assumption, but my point which I admit I made indirectly is that our public health policy program is not working as they said it would. Hopefully this strain is less deadly, and higher vaccination rates and better treatments end up reducing fatalities.
Thing of it is we’ll never really know. There is no control group. There is no way to gauge absolute risk with or without vaccines. It’s a strange virus in that large numbers never get any symptoms at all. Perhaps most would have survived without a vaccine anyway. Perhaps most would have had the same symptoms with or without vaccines. Any analysis will all just be post hoc analysis.