I happen to be a Canadian snowbird living and driving in Florida with a Quebec drivers license and auto registration which are totally in the French language so I guess the reasoning for a foreign language has some validity but.... in looking at mine I wonder what information on it is considered really difficult to understand for most LEOS. The Number? (in big letters), Name, address, Class, (Classe(s) ) a number... but that information likely varies greatly even between states, validity date (Valide le

expiry date (Expire le) ...... you get the idea!!!
Just another black eye for the Florida tourist industry.... but it won't likely stop me from traveling to my winter home. What will hurt is the lack of publicity when these 10's of thousands of Canadians coming down here each year unaware of this rule and they get stopped, fined, and especially..... can`t rent a car ... Most short term visitors who fly in, do this .....
When you cross the US boarder in a car or RV and asked where you destination will be you should not be allowed entry if you do not have the required documentation to operate there.
Remember it is a STATE law right now. Border Control officers have no knowledge of the many, many State laws in effect, nor could they be expected to (imho). The border control officers will not even ask for a drivers license unless you have no passport and use the US government approved new drivers license for identification instead. It is not needed or checked for driver qualification. (We use passports as they are required for air travel anyway....) And holding an IDP won`t help anyone decipher the Quebec auto registration in French, heh heh!!!!)
Government Money grab? The issuing body for an IDP would appear to be the CAA (Canadian Automobile Association), roughly equivalent to the AAA, unless you are considering the potential fine revenue collectable by the State of Florida....