I actually disagree, i think Truls has one of the best forehands in the world (easily the best in Europe) and the main thing is to play a bit like him and stop trying to overpower him with the first shot but to to put him out of position with strategic serving. One of the reasons why Hugo struggles so much with Truls is that with all due respect to Hugo, his serve is extremely straightforward and once Truls reads it, he can add juat about any spin he wants. Darko at least can keep Truls off balance with various placements and spin choices out of backhand serve. And then Wang has the ultimate advantage - a lefty serve which does pretty much what Darko's serve does.
Even with that Harimoto has a good enough short game.that he could have won today. A lot of it comrs down having weapons that don't put you on the back foot and refusing to play to your preferences if they feed the opponent's preferences as well. Truls clearly has worked harder on the problem, others need to do the same.