Joselu had a good time with Madrid even though it was short but he was able to make a considerable contribution to Madrid, his move to Qatar is certainly the right thing at this time after Mbappe arrival to Madrid, staying in Madrid is not a choice that he did take because it will only make his career worse because it is indeed fierce competition in the squad, especially the Madrid front line, Although he still has a good performance as a striker, it is undeniable that his age and stamina will be an obstacle for Joselu to compete in La Liga, although La Liga is not as competitive as the English League, but I think every player who plays in La Liga is required to have quite good stamina, especially since Madrid has a fairly tight schedule.
Moving to another team in a different league at this time is not a bad option for Joselu considering his own age, which is no longer young. And new players like Mbappe who will strengthen Real Madrid next season can still be used as future players for Real Madrid. Apart from that, Real Madrid management always has a unique way of releasing old players and also bringing in new players so that the team's strength will never decline significantly because the players released are always older than the players who are successfully brought in each new season.
I think the tactic of letting old players go and bringing in a new young quality player into the Real Madrid squad is what has been working for Real Madrid for ages to always be the Laliga and Champions League strong title contestants every given season.
Now, Joselu has let go, for Mbappe to step into the team. It will be like nothing really changed in the frontline of Real Madrid but instead, they made their frontline to be more stronger to go head-to-head with other teams for the title race. By next season, other old players will be let go from Real Madrid to bring in another young quality players. The changes of the old players to bring in young quality players is normal routine for Real Madrid every beginning of new season.