Perhaps not commercial pe se
But recall many an Amana and other brand microwaves just like one pictured.
They were in nurses and other employee break rooms used for mostly heating foods brought from home or elsewhere.
With no "defrost" or "low" setting such ovens by Amana or whoever weren't the most truly functional things around, but guess for some households they got the job done.
When you consider what most use microwave ovens for then and now; and what they are mostly suited for; that NOS Amana likely would suffice for most homes today, and outlive us all even with regular heavy use.