Yes, what could be more American than a Volkswagen-engined Plymouth based on a Simca design? Actually, big spenders could get the '81 Horizon with Chrysler's new 2.2 engine, which upped the American-ness to some extent.
The Omni/Horizon did its job, which was to provide a semi-homegrown econobox to help replace the captive-import Mitsubishis and keep the revenue flowing until Chrysler could start moving K cars into the showrooms and pay back that big government bailout loan. In fact, this platform continued in production until 1990.