That's quite likely. Though I'm not seeing any prospective names that seem really compelling IMO. Gyorkeres might be good. Osimhen looks great but is played by injuries. Isak is proven but I'm not sure he's in the level we need (plus I doubt Newcastle would let him go for anything like a reasonable price).
Arteta is definitely more relaxed about the 30+ age contract thing than Wenger was. And it makes sense, given that the likes of Jorginho and Elnenny are/were still able to put in a shift after 30 (albeit not for several matches back to back).
ETA: I mean this in the context of Merino being under contract until he's 32/33. I know he's only 28 right now.