One thing that could be done is to keep the fanfics away from him. Don't show him any new fanfics or talk about them in his presence.
The fanfic writers could try to improve the quality of their works. If they focus on staying true to the original characters and storylines, and also improve their writing skills, maybe over time Jason Grace's view could change. For example, if they do more research on the official works and avoid wild and untrue speculations in their fanfics.
Perhaps an open conversation could be had. If someone who is a fan of both the original works and fanfics can sit down with Jason Grace and explain the positive aspects of fanfics, like how they can expand the universe in creative ways and how they are a form of love for the original work from the fans. It might help him to at least tolerate them.
Chapter 161, "Who Told You That the Furnace Needed Someone to Light It?", is the clearest early answer because it turns Cold Beasts's situation into a concrete plot event. It opens with The reason why humans cannot withstand the low temperatures during... and closes on In the center of the third-floor hall, four to five hundred children....
Chapter 184, "Leap in Productivity, Expansion of Territory, Xia Chuan's Opportunity", is the clearest early answer because it turns Great Xia's situation into a concrete plot event. The chapter gives readers a real answer by opening on Behind the main hall of the temporary cabin, there is a small... and ending on Within just a month, Mu Dong managed to produce them?.
Chapter 135, "The Fearless Mirror Immortal [Three in One]", is the clearest early answer because it turns Xia Chuan's situation into a concrete plot event. The setup is To the north, the Cloud Mist Zone should be the territory of the Teng..., but the pressure keeps building through This stretches five or six hundred meters; is it intermediate or....
Chapter 166, "The Defenseless Mirror Immortal", is the clearest early answer because it turns Hong Guang's situation into a concrete plot event. It opens with Xia Hong, my leader, among our three thousand people, none have paid... and closes on Moreover, if He Yuanhun wins, it's a dead end for us all..
Chapter 198, "Unblocking Acupoints, Breakthrough Imminent (Part 3)", is the clearest early answer because Great Xia finally turns buildup into a real advancement. The chapter turns that into something concrete by moving from In the future, Yuwen Dao's Long Wu team, as well as any other team... to The beast tide took away 128 lives, including 12 from the....
Chapter 192, "Beehive Predicament, Surge in Earth-digging Realm", is the clearest early answer because Wu Tianxing finally turns buildup into a real advancement. The setup is Wu Tianxing's face turned grave upon hearing this, and he said..., but the pressure keeps building through Marquis Zhaoyang Hu is at the peak of his power, with the camp's....
Chapter 232, "Saving Lives, Putting on an Act, Xia City in Uproar [8,000-Word Chapter, More to Come]", is the clearest early answer because it pushes Wu Xiong into a new phase or setting. The chapter gives readers a real answer by opening on Peng Bo, a Superior Battle Body with the strength of Eight-maned, was... and ending on Clang...… The staff came down for another fierce strike; though Peng....
Chapter 253, "Short on Meat, Short on Manpower, Someone Delivers (Part 2)", is the clearest early answer because it turns Long Mountain's situation into a concrete plot event. Early on, Beehive 129, last night Hanqiong's 1259, with the newly added.... By the end, Our stockpile of beast meat is considerable; if the population....
Chapter 163, "Almost Annihilated, The Mystery of Gao Yu", is the clearest early answer because it turns Cold Resistance Level's situation into a concrete plot event. The chapter turns that into something concrete by moving from After tonight, everything will be completely different. to Not only that, Xia Hong also wiped the bloodstains off his left face..
Chapter 151, "Pioneering, The Growth of Xia Chuan [sorry, late]", is the clearest early answer because it turns Great Xia Camp's situation into a concrete plot event. The chapter turns that into something concrete by moving from Establishing the Pioneer Department opens a new path for advancement;... to Even if mistakes are made, we need to nurture these people first;....