Julian Alvarez was good and even more of a rounded player than even this Halaand we are talking about, Alvarez was simply just not going to get those minute at Manchester city because unlike the past where Pep Guardiola do prioritize players of his caliber or ability now he prefers the direct approach or players like Halaand whose quality are direct and this have won him the champions league, for me Alvarez made the best decision by joining atletico Madrid because they actually are one of the best in the world.
Julian Alvarez is like Inzaghi in that past and they belong to a type of player who look not easily recognizable on field, but they can make big differences for their team. Give them opportunities and Inzaghi, Alvarez will punish your team with goals to help their team taking advantage or winning a match.
I believe that Pep Guardiola actually wanted to keep Julian Alvarez in Manchester City but the player possible was like Cole Palmer. He no longer wanted to stay in Manchester City and satisfy with a substitution role. Alvarez wanted to leave and find opportunities to be a main player in another club, he need new challenge and upgrade for his career.
Now we can see, in a player injury crisis, Pep Guardiola no longer have good replacement for Haaland at a striker position and Julian Alvarez can play at different positions on field as well.