You shouldn't blame Arsenal fans if they are expecting so many goals from Gyokeres next season because the hype on Gyokeres is too much, and Arsenal fans are expecting him to live up to their expectations. Arsenal is a club that's good at set pieces, and they always create a lot of chances for their strikers, so I believe if Gyokeres is clinical in his finishing, he can be able to score 20 goals for Arsenal next season.
I agree with you, we shouldn't blame Arsenal fans for expecting many goals from Gyøkeres next season since the hype on the player was too strong. The player rejected several clubs and is only interested in playing for Arsenal. Gyøkeres must perform at the high level expected by fans and the team for the next season. The fans hope to see the Gyøkeres who scored many goals at Sporting CP last season, so he should not disappoint.
However, Gyøkeres has previously played for Brighton and made a few senior appearances before being loaned to another club, should get used to the Premier League environment easily. Despite the fact I am not an Arsenal supporter, I have high expectations for the team's success next season because they are gathering key players.