Since Journeys has ended for Goh, he's Goh-ne, which means it's time to see what his real purpose was to you. What was it?
(Yeah, I had a topic with a poll, but I decided to delete it because it seemed more...distracting, shall we say. Ha ha.)
Promote Deku's voice actor, return with the co-protagonist act, have a less bloated cast than SM, promote Pokémon GO's mechanic, have less CotD, by having him catching PotD, which happened even less along of the road...
In universe, I think it was just to give Ash a partner who could be a contrast to him, but also have the same drive and cheerfulness for meet new pokemon. That part of the character they got right.
My problem was with the captures. Go is the character with the biggest pool of pokemon in the show and, despite some of his 'mons have very funny or distintc personalities, they weren't as used as I wish, while the Galar starters got the spotlight. I'd have love if misdreavus, darmanitan or beedrill had more to do or develop a few of the others at the lab.
In a way, it could be better if Ash could have more than six 'mons this time, or if Oak's lab was the main hub, so at least we could see Ash's pokemon trying to help with Go's.