Hey Nuno,
I'm not sure whether this thread is about horrible guests in general or about French guests, but since I am French, I feel obliged to join this conversation.
We certainly host less French here than you do in Ireland, but we have our share, also because I can communicate in French.
This is a matter of generation, first, and I can say that about almost all the nationalities we have hosted.
The 20-30y old guests we get are undeniably less respectful, less caring , less clean than the previous generations, in general.
If they come in big groups, nightmare ...
And usually, the less guests pay, the more they expect. The rare who gave us 4* in value weren't paying the high price and were all careless or dirty.
To rate 1*, either they didn't like you or they only like themselves, or there was something that ruined they stay.
It happened to us once, but it was a hateful review from Koreans who didn't want hosts and rules, and Airbnb removed the review.
Have you ever reported 1* reviews that you found totally dishonest?
Common French tourists tend to count their money, try to get rebates for everything, compare everything to the same in France, and complain very often. Plus they often don't speak English. They aren't the cleanest guests you can host.
More upscale ones aren't like that. And the same can be said about other nationalities, indeed.
We had a 30ish French girl for one week, who was an absolute mess: dirty, stingy, unreliable ...
But we also had a mature French couple for another week, who left our place almost as they found it.
Some guests just need a couple of nights to dirty your whole place, in comparison. We've seen that from Canadians, Germans, Italians, Koreans, etc.
It really depends on what kind of people your listing (price first) attracts.
With Instant Book, you can now see the ratings of your guests after they book.
It's not about wine or cheese (stereotypes), it's about the characters, beyond the nationalities.
When you see dubious ratings, maybe you can engage a discussion to detect potentially troublesome guests, and eventually cancel bookings because you don't feel comfortable.
You shouldn't kill yourself to please impossible guests, you should just avoid hosting them.
Have some requirements and ask them to provide info, you will see their reactions ...
