I agree completely. A dance is 3-4 minutes and at that age, there should be a volleyball to basketball diameter between the chests of the dancer.
There is no good reason to not be polite and do one dance with someone one time.
I started dancing in 2001 after my ex-wife divorces me. It did tremendous things foe my emotional health, especially since my ex was not an affectionate woman.
There were many excellent women dancers who asked me to dance when I knew almost nothing about dancing. I got to be an excellent social dancer in very short order. Not saying I was addicted to dancing, but I once went dancing 21 nights in a row.
I attended a lot of Christian singles dances over quite a few years and always made it a point to ask women, even the fat ones, who were there for the first time to dance and offer encouragement.
Proper dance etiquette requires that you sit out the rest of a dance if you turn someone down. If you need to sit one out because you need a rest, the most polite thing to say is that you need a rest, but would be happy to do the next dance with them.
Saying yes to a dance request is just a response to someone who might need some affirmation. It could change their life knowing someone accepted them even in such a small way.
This is a kind thing to do.