Seems pretty obvious why the Russian military would want to expand the front creating logistics problems for Ukraine. Creating a large front has literally been the doctrine since WW2 times. Ukraine is now stuck in Kursk because politically they can't just pull back, so now they have to keep feeding valuable resources into a battle that has zero strategic value for Ukraine. Meanwhile, this is weakening actual strategic places like Pokrovsk. Once Russia takes that, it splits the front in half between north and south which will make it impossible for AFU to reinforce its southern forces. This will create a huge cauldron where Ukrainian troops are trapped. Even mainstream western media understands this, yet here you are.