Sainz had a couple of good races this year (Monza and Singapore) which were, for me, the only real times I’ve seen him be properly impressive as a Ferrari driver. Even then, in Monza Leclerc had more race pace.
Ultimately he was ok as a number 2 (Rubens level) but was often given equal number 1 treatment, which ended up costing Leclerc. You could either treat him as a proper number two or bring in someone deserving of the equal number one. They chose the latter.
I’m intrigued, somewhat excited but also cautiously sceptical about Hamilton joining - it will certainly be interesting but I don’t know if it will work. I think it at least shows ambition. I’m most buoyed by the fact that he wanted to join likely bodes well for Ferrari’s development prospects as Hamilton has a Fangio-esque knack for getting in the right cars at the right time.