The Kushners are “Modern Orthodox”, which is not part of right-wing Orthodoxy and somewhat closer to “Conservative” (liberal) Judaism while being more ritually observant than that movement.
Embrace of anything on the left always requires ignoring the scriptures, same as with nominal Christians who do so.
“Conservative” Jewry is far MORE Conservative than you claim. You’re thinking about REFORM !
“Modern Orthodox.” Is that like a “Kosher Agnostic?”