Because France does not have nobility. Thus, anyone claiming to be French nobility is a figure of fun.
From the dictionary:
pre·tend·er
From the Wikipedia:
Prince Charles-Philippe Marie Louis of Orléans, Duke of Anjou (French: Charles Philippe Marie Louis d’Orléans; born 3 March 1973, in Paris) is a member of the House of Orléans. He is the older of two sons of Prince Michel d'Orléans, comte d'Évreux, and his wife the former Béatrice Pasquier de Franclieu. His paternal grandfather was Henri, Count of Paris, the Orléanist pretender to the French throne. As such, Charles-Philippe takes the traditional royal rank of petit-fils de France with the style of Royal Highness.
The grandson of a pretender is a pretender.
Nobility has been obsolete since George Washington bailed out after two terms, setting the precedent that there should be no King of the United States. If the United States does not need a king, no nation does.
Not that there is anything wrong with the Pretenders!
Neither Washington or anyone else removed nobility from noblemen. They are noblemen forever, — unless, of course a narrow circumstance emerges when they are disgraced and then a court capable of deciding such matters removes the status. In the US the titles of nobility are not recognized. That is all.
Of course a noblemen — or anyone can be a pretender to the throne. That is no different than, say, a GOP pretender to the presidency. Different word, same meaning. If His Grace ever ascends to the throne, God bless him and God bless the French people. Clearly he will do good. As far as I know he did run for presidency too. I don’t’ know, however, if His Grace ever advocated a return to the monarchy. At this point there is no environment in France to have a realistic expectation of a restoration. However, if the royal house of Orleans keeps educating the French public about right and wrong, it already will be doing the job of the royals.
You might wish to look up what a pretender to the throne/crown IS before stating that this man is a “pretend” prince, using the word in its common American usage.