There are, of course, other lines of businesses for start-ups to get into.
It is probably true that if you're looking to disrupt how employment markets function, France is probably not a great place to focus your initial efforts. But there are lots of ways to make money outside of that.
That's only true until your business threatens a competitor with more political influence... in countries where the laws are written that way. (The USA counts as such a country, though we don't do it as much as france- look at how much protection the cable and wireless companies have.)
If your business model is "bypass the law and hope you can get big enough before anyone notices", this kind of setbacks are bound to happen. It happened in France, it could have happened anywhere.
On the other hand, there are thousands of people creating startups without trying to hack the law, and they are doing just fine in France.
It is probably true that if you're looking to disrupt how employment markets function, France is probably not a great place to focus your initial efforts. But there are lots of ways to make money outside of that.