I could almost agree with a win-by-2-rounds scenario during "golden cap" time, but the problem is the park-the-bus strategy that sometimes comes into play. However, if there was a round-reset if the round isn't won in 10 minutes, that would incentivize defense to go all-out which limits their need to push, thus they employ the park the bus strategy and this could be either positive or negative in the outcome of players giving their best shot pushing/defending.
Parking-the-bus stagnates the game in golden cap, but if there was a scenario where golden cap rules are in effect, but you need to win 2 golden cap rounds out of 3, it would almost obligate parking-the-bus, but allow for more opportunities to redeem with a clean midfight. Gives teams a full chance to fix their mistakes, and the limit would be a 30 minute "golden cap" tournament-config, assuming whoever won mid just turtle'd the map and it went 1-1 for the first 20 minutes.