Arsenal is always slow to things like this. I don't know the plan of their management and which players they want to sign. It's clear that the players that they already have in the club cannot win the EPL title after four consecutive attempts. The need of a few new players to add to the team is very important for a stable performance throughout next season.
Gyokeres is a serious target for Arsenal in the transfer market to fill the front line but so far there is no certainty even though there are a number of other names that have also been linked with Arsenal so far. Arsenal's movement is a bit slow at the moment and maybe Arteta thinks there is no need to recruit a number of players for other positions because so far the players they have are very good.
Arsenal's weakness lies only in the front line position because they do not have a pure striker who can improve the quality of scoring goals. Gyokeres' name is quite associated because he is a player who is very much liked by Arteta but if they don't move faster then I doubt Arsenal will succeed in bringing him in.