Sorry it's taken so long to get back to this.  The problem with dropping rinputsoptions is that IE11 (and others) offers the .disabled and .isDisabled property on non-input elements, such as <div>.  So basically, 
we want the following test to be true
$('<div>').filter(':enabled').length === 0 
and the only way to do that with IE is to opt-in everything that *can* be enabled, so as to exclude everything for which "enabledness" should not apply.