Instead of trying to avoid infection and most likely failing, a more productive approach is to focus on reducing the risks of a bad outcome when you inevitably do get infected. For most people that means getting vaccinated plus resolving any major risk factor conditions such as obesity, type-2 diabetes, and hypovitaminosis D.
And you didn't answer the question. Which specific "experts" claim it will be possible to avoid infection?
https://www.theguardian.com/commentisfree/2022/apr/03/people...
And the so-called "People's CDC" isn't even a serious scientific or medical group. Unlike the real CDC, they're not doing any original research or useful analysis. It's merely a political advocacy group. There's nothing wrong with political advocacy but don't confuse it with actual science.
I gravitate towards those that say something can be done; that we have both the science and the ability to do it, though I'd say we do have a lot of people with a lot of power that want to tell us to give up on the precautionary principle.