In terms of achievement, Raducanu's victory at the US open was unprecedented.

I'm not really into tennis enough to comment on whether she's a "personality". For awards like this it's always a bit of a popularity contest, so you're never going to please everyone. It's more about who has captured the public imagination the most.

Were there better candidates?

It's a shame a lot of sportspeople these days are counselled to only speak bland niceties, for fear of offending. Post-match interviews are almost always filled with "all respect to him/her/them", "taking each game as it comes", "just trying to work on my game". "there are 100 other people/teams who could beat us/me" etc. It seems like it's a void that needs filling with some genuine opinion and personality.