I've found the opposite to be true - that the French are impatient when you try to speak French

Au contraire IME - they appreciate it and will be more patient with you than the more common it seems american who blurts out DO YOU SPEAK ENGLISH in a demanding way

In any case the overwhelming number of ordinary French folk that have met simply do not speak enough English and must speak in French.

Though my French is rather lacking i can be understood and in places like tourist offices i have got the retort 'it's nice to hear an American speak French'