..However, its the simplest and most sure way of doing it..its the one way that means any basic Power Supply engineer can understand it and maintain or modify the design.
There are methods such as the " Single stage, Bridgeless PFC'd Isolated Cuk Converter"...however, few people in the world can understand this.
I wouldnt mind betting that the use of multiple smaller modules means that the thermal situation is less severe than in a "single stage" type design, -this would mean it will last longer.
Also, the redundancy Easy Peasy spoke of means that if one module fails, the others can still work.
Also, the size of the modules, limited to 2.5kw, means that off-the-shelf components and cores can be used, instead of custom stuff.
I also bet that this "multiple module" method means its more efficient than any of the "single stage" methods. -And with millions of electric vehicle chargers, efficiency is surely king.
The method of the top post looks poor, -until you look at the alternatives.