Yeah, Harden was forced to play the crucial game 5. He might not be able to make enough points in his 45+ mins, but sure it was the Coach's strategy to divert the opponent's defense instead of focusing on Durant.
As you noticed Harden played as much as Durant's full mins even with the bad shooting percentage and a struggling recovery from a bad injury. All that just to avoid Durant as the focal point of the whole Bucks defense.
I applaud Durant for such amazing performance. Stepping up when everyone needs him in a crucial game, not to mention the risk Harden has been facing playing 45mins comes out fresh from the injury.
Bucks blew away their only golden opportunity in the series to beat the Nets, now they have to win 2 games in order to beat the Nets in the series and that would be tough because once Irving is fully recovered, they will have to face the big 3 of the Nets.
Their defense on Durant was not carefully planned, they should double him and put somebody on him as he was the only one who is consistently helping the team to win, yes Green was there but if they can stop Durant, Bucks would have won that game.