Barella, I can agree, but Zielinski is doing almost nothing defensively.
Agree that Belligham, Valverde and Barella are better players and maybe some even earn less, but: we have to also consider how much it would cost to buy as effective player (if it would even be possible), as you have to count the fee also in the annual cost.
This all doesnt matter though if that form is only until he signs new contract though - i dunno what Rabiot real motivation is, but imo looking at current state it makes sense to offer him extension on the level of his current salary, but shouldnt go any further.
yearly salary of Napoli starting midfield that'll win the league in 22/23:
Lobotka - Anguissa - Zielinski
2.8m+0.5m - 2.7m+0.3m - 3.5m
yearly salary of Milan starting midfield when they won the league in 21/22:
Tonali - Kessie - Bennacer/Diaz
1.3m - 2.2m - 1.5m/1.5m
yearly salary of Inter starting midfield when they won the league in 20/21:
Barella - Brozoviz - Eriksen/Vidal
2.5m (now 5m) - 3.5m (now 6m) - 7.5m/6.5m (now cut)
To me it just seems perverse to renew Rabiot on 7m+2m salary, obviously he's not worth that much. The normal practice would be to invest in 20-25yo players and when the squad needs new blood or a new coach comes in and requests different profiles, you can always sell these guys and recoup that investment like we recently did with McKennie, Bentancur, Kulusevski, de Ligt etc. If you're just looking at the yearly cost on the books - transfer fee / contract length + yearly salary, then yes, the "free" agents on crazy salaries might look slightly cheaper. But long term signing players on transfer fees is significantly more cheap and gives you a lot more wiggle room than dishing out crazy contracts. Not to mention what overpaying players out of contract does to renewal negotiations with other existing players