The goal main and ONLY goal of a BR game is to survive and be the last man/team alive. Fighting more does NOT increase chances of achieving that goal. So it makes sense to promote the correct play in ranked mode. In general getting kills, especially early game kills, should not be rewarded at all, because that goes against the idea of the whole game.
Leaving superior position to get kills outside of the zone should be punished, not rewarded. Awarding points for fighting promotes incorrect gameplay - it should NEVER be beneficial to sacrifice win% for kills. Fights should only be taken to increase chance to win (e.g., fight to take superior position, take a highly advantageous fight for loot, etc).
P.S. If everyone played correctly and aimed for just survival, it would NOT be easy to even get to top10 without being FORCED to fight. And yes, the game SHOULD be very passive overall with short bursts of intense action. This IS a survival game after all, not a deathmatch.
P.P.S. How passive the game is, is generally determined by match duration, which in essence is time to last zone. If the last zone closed within 8 minutes, the matches would be very intense (and quite random though) by necessity. Hmm, maybe a blitz mode (maybe during some timed event) would be fun for a while (would get boring fast though).