Dude, no. SSJ2 Trunks is not stronger than SSB Goku or Vegeta. During training, SSB Vegeta had to give himself a major handicap so that Trunks only needed to hit his face to consider it a win, and even then Trunks failed until Vegeta had powered down to base.
Even in his rage boost during the future, Trunks was only comparitively strong when put against Future Zamasu. SSJ2 Goku had stomped Present Zamasu, so it's not that much of a longshot.
Also debatable whether Super Trunks is stronger than SSB Goku or Vegeta. From what I saw in the anime, only indication is Trunks is now in the God-ki league, but nothing to clearly indicate his power surpasses them.
At this point, I'm just glad that anyone is at Goku and Vegeta level, and it's not those two Saiyan big boys stealing the scene for a change. If someone deserves the attention, why not let the Dragon Ball breakout character do it? Remember, Trunks was the second character ever to attain Super Saiyan, and for a while was the strongest character aside from Goku.
By the time of Majin Buu Saga, any character who wasn't a Saiyan became irrelevant and got left behind. But after Beerus showed up, any one who wasn't Goku and Vegeta was irrelevant and got left behind. Future Trunks finally changed that, which gives hope to the other characters.
As for Gohan. Guess Toriyama or Toei just likes his role as the Saiyan Yamcha, and justifies it through Gohan being happy not fighting, as was what he wanted back when he was 4 years old but was unable to pursue due to the constant threats to the Earth.