He's not stupid, thousand's of refugees are flowing out of Ukraine into Poland every hour. Sad to say but when the dust settles and the new pro-Russian government is in place the pro-Russian Ukrainian refugees will return, the anti-Russian ones will not.
Likewise many of the anti-Russian Ukrainians will die in the war, the pro-Russian ones, probably will suffer a lot of casualties too, but the end result will most likely be a shift either back to Ukraine being mostly pro-Russian due to exile/death of the anti-Russian Ukrainians, or a shift large enough to make the country "manageable"