Appropriate response to misattributed title?
The standard answer to such issues is to ignore. By and large, these situations arise because the editor etc. did not care to look up the recipient's real title. There is no malicious intent, actually there is likely no intent at all other than trying to use a catch-all title that the editor assumes will not offend anybody (typically Dr. or Prof.). No harm is done by not rectifying this error, and indeed spending more than a short chuckle on this is too much effort.

(also, being addressed by the wrong title is, at least for me, so common that I mostly stopped noticing it)