I feel like this exchange may have been a manufactured strawman, because the flaw in the shower argument is obvious: no one is mandating showers, and there are

I feel like this exchange may have been a manufactured strawman, because the flaw in the shower argument is obvious: no one is mandating showers, and there are no widespread objections to showers. Even insofar as minimal personal hygiene is implicitly required, it's left entirely up to an individual's conscience how to achieve it. A fair comparison would be mandating "either a vaccine or avoiding crowds in indoor spaces or any similar measure", since both of those are known to significantly reduce (but not eliminate) the risk. (How effectively they do so is beside the point of the inapplicability of the shower analogy.)