I think you might be confusing the categories for quality. Giroud/vermaelen/podolski are players who, while they weren’t quite to the standard of Fabregas, wore the shirt with pride, didn’t want to leave the club and ultimately we’d welcome back here warmly.
Sanchez is in that category because he’s a snake. Wanted to leave Arsenal for a domestic rival. Kept quiet about it. Made some cutting comments about winning trophies after he’d joined Manchester United.
Fabregas belongs with them.