The best striker will need to have many conditions in this season: goals scored, assists made and titles with his club. It is similarly to Ballon d'Or which often is awarded to a player who wins Champions League, Euro or World Cup title in a same season. A striker can score many goals, and win the Premier League goal scorer of the season but is he considered as a best striker in the league, it is not simple and easy like this.

It's not about emotional assessment on a striker performances individually but also his club performances and achievement at the season ending. By the criteria, I agree with you that Isak has highest chance of becoming a best striker in Premier League this season as he will receive very good support in Liverpool while the club has good chance of defending their title.