No one ever said you HAD to pause cancel. If you want to play the game fast, then it's a must. But if you're just playing casually and taking your time, you never have to do it. If you want to pause and leave that BHB on screen, just open the Challenge list or press Home.
And I totally disagree with speedrunning being the game's goal. Just because the game gives you your time at the end, you're supposed to get the lowest time? No way. Plenty of games keep track of your time, and aren't really prime for speedrunning. Take RPGs for example. Though it can and has been done, I doubt you're playing them for time. Hell, I don't think the majority of people really give a damn about their times in MM9, anyway. They'd be happy just to beat the game.
They don't show the time at the end to show you what to improve. It's just there as a convenience, if you're curious how long it took you to beat the game. It's nothing new to Mega Man, either. X5 and X6 showed you at the end, and X7 and X8 allowed you to save a final save with your clear time visible.