We loved Luca for its gorgeous animation and the sweet story. I particularly loved how strong and feisty Giulia is!
As for the criticism, I see where it's coming from. I know that some people were also complaining about the Disney movie Raya featuring Asian American actors from East Asia (Korea and China) instead of Southeast Asia (which is where Raya is set).
Are any of the main Luca actors Italian American? I can't tell from the names but I see some supporting characters have Italian names (like Giulia's dad and Ercole).
I think hiring more Italian voice actors would have been lovely and more authentic than Americans faking a slight Italian accent. Yet it's not enough to convince me to boycott the movie.