Morals are subjective.
Many people would say paying for sex is morally wrong, regardless of the age.
Many people would say an age gap this wide is morally wrong, regardless if it's in exchange for something.
Many people would say it's morally wrong to have sex out of wedlock, regardless of age or exchange.
Many people would say that two consenting adults is all that matters.
Some people would argue what "completely harmless" means.
And some people would argue over the legal or moral differences between "adult" and "of age".
What I would personally add to the conversation is that a condom has absolutely nothing to do with the situation when you're questioning what's "morally" right or wrong.