That is what Arsenal always faces and it is not always consistent because when they play well, there is always something that makes their performance decline due to various factors. And if we talk about some players who are injured or some key players who are injured, it will definitely affect the results of each team's match. As we see and know Manchester City and this applies to all teams including Arsenal, and injuries to players, especially key players, greatly affect the team's game. However, this season's match is still very far away and Arsenal, including other top teams, still have the opportunity to compete to be at the top of the standings if they make changes and also find ways for their injured players to recover quickly.
You can say the team is not complete. Every club needs to have a replacement for the most important positions so that when injury occurs they will see someone to still make the same contribution needed in that position. Injury shouldn't be an excuse for a team that wants to win the league. There is no how they can play all the games in the entire season and not have one or two injured players.
I don't think Arsenal is ready yet, they are yet to get the required players. Right now, Odegard and Saka's position should have a suitable replacement. Then i think the team will be properly ready.