I think less of Shakespeare and Macbeth because of the pandering. And I don't think it is unreasonable for others to do so too. What I find unreasonable is indignation at having the temerity to think so.
Vergil's Aeneid changed and added to Roman mythology in the pursuit of "patriotic" themes. I think his feelings about the value of this kind of creativity was pretty concisely and vividly expressed: On his deathbed he asked that the poem be burned.
He was a professional writer whose work has been remembered for two thousand years, so I think his opinion is worth considering, don't you?
Using the same names and plots isn't any less creative? How is it less creative to use some of the very same dialogue? As opposed to, the owners of the rights to a property have paid for the one, but not the other? And, what is that to nonprofessionals who don't have a living at stake?