Exactly. Not just France. Most countries in Europe don't have monarchies: Italy, Germany, Austria, Poland, Czech Republic, Greece, Portugal, Iceland, Finland, Switzerland to name a few.
Can you imagine a tourist saying, 'Why would I visit Italy, or Germany or Greece or Austria? They have no monarchy, not interested!' Wildly unlikely.
Do people think that Britain has nothing interesting to offer tourists apart from the monarchy?
It's also fair to note that several other European countries HAVE retained monarchies (Spain, Norway, Netherlands etc) but maintain healthy numbers of tourists who are drawn by other things. Or look at Japan - they have the oldest continuous monarchy in the world, but it's hardly one of the top reasons so many people want to visit.