Well don't be too sarcastic, well atleast they actually signed a player before type before the transfer window actually ended although many arsenal fans think and believe that the signing wasn't really needed like the way they actually needed to sign a striker to aid them in goal scoring so as to improve their chances at fighting and securing the league for a very long period of time.
Arsenal keeps making signings that appear like they are not needed, they have a good squad and they lack striker as everyone can see yet it looks like they have continually not wanting to sign a striker at the moment and that could be one of the reasons for that sarcasm, even some arsenal fans that I know make light jokes about Arsenal sometimes in for of such sarcasm but I believe Arsenal and their management has everthing under control as seen in their performance, their level of brilliance is such that they appear sometimes like they have the striker we are expecting they sign. Let's hope that before the end of the transfer window, they will be able to make some transfer deals and get a striker.
The coach is the one that signed zubimendi and I feel he has his reasons too because he is the one in charge of managing the club although the entire world tend to see the effects of not having a pure number 9 in the squad but truth be told since that time arsenal haven't been that bad either atleast they score goals and also win games but the number would add an extra edge to the squad but if the coaches doesn't feel the urgency then he will bear whatever consequences that follows the action.