If I had to play devil's advocate - Edu/Arteta have assessed that none of the options add much to the squad and signing half baked players leaves us with deadwood that we're stuck with for several seasons. Better to keep the powder dry for one of the tier 1 options
That being said, I'm not sure I can explain why we wouldn't push for a loan for Sane/Gnabry/Sterling/Sancho - it's not just talent at this point. We need numbers too and there's enough out that that would represent an incremental improvement.
Failing that - we're reliant on Jesus and Martelli stepping up in a big way.