1. My bad, I was counting only GoW 3, and GoW 3 (like you wrote only mainline game on PS3) is around 5m.
2. Talking about sales, every main Uncharted game sold better than best selling GoW game until last GoW game. Of Course that when some game is released is important, its not same if you have launch of strong game on install base of 40m and when you have launch of strong game on same platform but on intall of almost 80m, you can bet that Uncharted 4 would also had much stronger launch if actualy was launched on install base of 80m instead of 40m.
3. I was talking only about last two generation, and Drake was more popular than Kratos until last GoW game.
1. GOW 3 sold 5 million by May 2012, so it could easily be at over 6 million by now on PS3 alone.
2. You're wrong going by VGC sales. Sony published GOW 3 sales on PS3 as of May 2012 and it was higher than Uncharted: Drake's Fortune.
Install bases don't matter at a certain critical point. Uncharted 4 released on a 40m userbase which already had Uncharted: Nathan Drake Collection so most Uncharted fans already had a PS4 by that time. The other 40m userbase makes little difference to a game like God of War which will sell to a fraction of the install base and that fraction will grow smaller as the install base grows, but not sell more if say PS4 had sold 120m units.
Its different for a game like The Legend of Zelda Breath of the Wild which continues to sell with the growing install base and shows that its initial sales were limited by the install base. Uncharted 4 sales slowed down that year till Sony bundled it with PS4, and Nathan Drake Collection benefitted massively from the bundling. I got the Nathan Drake Collection bundle when I didn't want it, it was the cheapest PS4 at that time. Same with the Uncharted 4 bundle.
3. Kratos was a playable character in MK 9, Soulcalibur BD and a boss in Shovel Knight. Drake has made no appearance in third party games. If he really were more popular, why did these companies choose Kratos to sell their games.