My husband and 3 other travelers are planning a trip to Normandy from Virginia next Spring. Flights into Orly are several hundred dollars cheaper than into CDG. If they are planning on taking a train to Caen (then renting a car there), are trains regularly scheduled from both airports? Any reason not to fly into Orly if it’ll save $500+ for the four of them?
Go for Orly! There aren't any trains to Normandy from either airport, you have to go to Gare Saint Lazare station in Central Paris. That trip is slightly quicker and 15€ cheaper by cab from Orly.
I've used Orly twice and we liked it. It's not as fancy as CDG, but smaller, faster and easier!
"are trains regularly scheduled from both airports?" - your question is ambiguous.
Yes, there are trains from both airports into Paris. If you want to go to Caen you need to get to Gare St Lazare in Paris by métro, and a long-distance train from there.
Both airports are equally convenient/inconvenient for getting to Caen.
My first time to Paris was landing in Orly. That was in July 1973.
If the savings can be had for choosing Orly, why not choose Orly? I would.