What is an “appropriate amount” of cleavage for work?

This was a discussion my co worker and I had at work the other day and I thought it’d be interesting here.

Both of us are opticians within 10years of age from each other so about the same age demographic. Both of us have larger chests so some shirts we choose to wear a tank top under to limit the amount of cleavage we show. The job requires is to do a lot of moving be it up and down from our desks or even sometimes up in the patients face so we can get accurate measurements. Our desk sits a little lower than the patients because of the counter top so cleavage is almost inevitable.

I was reading our reviews (most of them 5 star) but one stood out to me. This person thought our customer service was great, but our attire was “completely unacceptable and unprofessional for an optometry office”

For reference this pic is about the most cleavage ever seen and very similar to the way my coworker and I dress. Our dress code is business casual No jeans. But we don’t really get much comments on our dress so it’s weird when it does happen

Our office is made up of 6 employees. Dr+2opticians+2interns+1 lab tech. Our lab tech is the only male staff we have. So maybe that’s why cleavage has never been a topic of discussion?

Should my coworkers and I be aware of the discomfort our cleavage brings to others? Or should we “write off” the negative comments?