Sturridge was a key part of our exciting 2014 team. He performed in many big games, therefore, he had credit in the bank.
Naby has been here for 3 years and I can't remember him dominating any big game which is why we paid £50m for him. The only top top performance I remember was against Burnley in December 2018.
He was our best midfielder when returning from the Covid break last year - and in that time racked up 2 goals and 3 assists in a time when the rest of the team basically went on holiday after sealing the title win.
Or compare that to his performances for RB Leipzig, when he was considered in the best 2 midfielders in the BUundesliga for a season or 2 (yes, alongside Thiago and ahead of the likes of Goreztka, Kimmich,etc) - and that as a 21 year old in a new team in a new country.
So yes, whilst you may say that you haven't seen him play "in a top game and dominate it for us", to me there is plenty of evidence to show that there is a very good player in there from both his team at RBL, and the odd occcasion he has been fit for long enough to player 4-5 games in a row for us
So now the question is probably - do we try and sell him this summer at a loss, or hope that with a proper pre-season he can either improve to the point he is more useful for us, or we can sell him for more next summer. If we assume we are losing Gini this summer (who has been poorer than Keita these past 18 months IMO), Hendo and Fab have both shown that they are capable of getting niggles here and there, and Thiago has consistently been injury prone for 5+ seasons now (in the previous 6 seasons for Bayern as mostly first choice, he started 23 or more games only in 2 seasons), I can see why people would want us to cash in and go for someone who can walk straight in and strengthen our first 11 whilst remaining fit for longer.
My thought is we have other areas we should look to strengthen this summer (CB, attack with Salah and Mane missing 6 weeks of next season and Bobby's form disappearing), so keeping him is preferable