I'm not an expert on the subject, but are there many French choreographers working in the neo-classcial tradition with similar international profile and status as Wheeldon/Ratmansky? If not, and BM wanted to introduce more high-caliber neo-classical works into the rep, then he didn't have that many choices.
I'll admit that even as someone who prefers the American/English neo-classical tradition, the amount of woks by anglo choreographers seems surprisingly high. On a second thought though, none of the choreographers are new to POB. Balanchine created works for the POB himself and is, after all, the overarching figure of 20th century ballet. The works presented this season, like Theme and Variations, is probably much more "purely classical" in its language than all those full-lengths reworked by Nureyev. Robbins the POB already danced under Lefevre, and perhaps BM thought the inner theater and emotional depth of his choreography would be closer to the French neo-classical tradition, if there is one. Opus 19/The Dreamer and Goldberg Variations I feel are both great vehicles for the POB dancers. Mcgregor I never really liked and consider his works as contemporary dance en pointe, but he too, was invited to create works for the company by Lefevre. Wheeldon again is a choreographer working with the classical vocabulary whose ballets could arguably better showcase the dancers classical training than many "contemporary spectacles" the company danced in in the past.