I feel like when you look at the calibre of right-backs at other clubs, Bellerin currently doesn't look close to the level of any of them.
Forget the traditional top 6 clubs for a moment, look at the rest of the league for example:
Leicester have some fantastic fullback options - James Justin, Ricardo Pereira, Timothy Castagne..
Everton have Godfrey and Coleman.
West Ham have Coufal, who has been great for them.
Southampton have Kyle Walker Peters, who has been excellent for them.
Aston Villa have Matty Cash, who has been one of their best players this season.
Brighton have Tariq Lamptey.
ALL of these are options I'd prefer instead of Hector.
I agree that someone like Max Aarons or Lamptey would be shrewd business.