you don't even have to go that fast. bearing in mind it's endgame content and if you are really struggling to keep time you don't deserve the high end rewards. also if you think the normal nightfall is speedrunning then what would you call the prestige nightfall where you have like five less minutes and enemies are 300 light? watch the legend himself's prestige nightfall clear from last week and then reconsider your definition of speedrunning.