I used to live in Lyon - wonderful city.
The football stadium is about 15km out of the city, in an otherwise dodgy neighbourhood. The union team play at the old football ground at Gerland (where GB won the World Cup), which is closer to the city, but still not ideal.
The city would be a tremendous place for a sporting festival - there are few better in Europe to visit - but the grounds don't lend themselves.
Around ten years ago, I was party to some information behind a Lyon bid to join Super League. A friend of mine was interpreting for them and came to me for the intracacies of rugby speak.
It never went anywhere, of course. I'd be surprised if they ever agreed their own plan and I don't believe it ever went anywhere at all.