I think Mews capture was hinted way back in the darkest day story arc. I do recall a while back that there was a promotional poster during the darkest day arc, which featured Ash and Goh alongside a picture panel of pokemon (dracovish, mew, suicune, zapdos, zacian, etc) in the background. Since watching the anime, nearly all of those pokemon depicted on that panel have ended up playing some type of role in the story or being a companion of Ash (Dracovish, Zacian) and Goh (Suicune, Zamazenta).
Based on how the story is moving forward of progressing Ash and Goh story, Its unlikely that the anime would introduce a Mew story arc centered around Goh's goal, and not have him catch it towards the climax, unless they plan to keep Goh as a main character in the future.
I'm not too thrilled of Goh getting mew so reluctantly, especially since he hasn't caught very many pokemon in a while. I was actually hoping that by now he would have caught over 200 or 300, but oh well.
Based on how the story is moving forward of progressing Ash and Goh story, Its unlikely that the anime would introduce a Mew story arc centered around Goh's goal, and not have him catch it towards the climax, unless they plan to keep Goh as a main character in the future.
I'm not too thrilled of Goh getting mew so reluctantly, especially since he hasn't caught very many pokemon in a while. I was actually hoping that by now he would have caught over 200 or 300, but oh well.