Here I am, using a 185 dpi display, and the font of XTerm menus¹ borders the unreadable small.
Investigating XTerm's XResources, I found a promising name but
$ xrdb -merge
XTerm*SimpleMenu*menuLabel.font: -*-helvetica-medium-r-*-*-*-180-100-100-*-*-iso10646-1^D
$
didn't help.
Is it possible to specify a larger font for XTerm's menus?
1 The fonts of the VT100 widget(?) are perfectly fine, this is not a question about changing the fonts of the XTerm main window.