It’s a class thing. As much as it makes us uncomfortable, Britain is a hugely class-based society. And we choose our baby’s name either due to being influenced by our class, or to try to appear a different class to the one we are.
Upper-class and upper-middle-class people don’t call their children Kaiden. There are some names which are exclusively upper class and the rest of us look ridiculous if we emulate them (they are ridiculous too, but they get away with it because of the massive buffer of privilege they have): Jolyon, St John, Septimus etc. The names of Jacob Rees-Mogg’s children, basically. These are paradoxically often names which are rejected by the truly upper class (ie Royalty).
Then there are names which the upper and middle classes both like and are favoured by royalty, but they are not as commonly chosen by the working class. Think Edward, Elizabeth, Henry.
Then there are names which are popular in all classes and it’s genuinely hard to tell a person’s background from the name alone: Matthew, James, Charlotte, Thomas, Harriet, Grace, Georgia, Victoria would be examples. There are loads.
Then there are names which are more exclusively middle and working class and as likely to be chosen by either. These tend to be popular and come and go in waves. Currently I would put Evie, Lily, Oliver, Harry, Ava in this category. Historically you’d be looking at names such as Gemma, Lauren, Nicola.
Finally there are names which are more exclusively working class. Kaiden, Jayden, Neveah, hyphenated names such as Lillie-Mae. There’s nothing wrong with these names! But they are definitely associated with a working class background, rather than being neutral.