Good question. I have mixed feelings.
On one hand, I’m not a fan of billionaire romances, especially in Christian fiction, because of the underlying unstated assumption that money will fix any problem.
On the other hand, I’ve read too many books where the plot centres around money troubles (often caused by medical issues), and it’s refreshing to read a novel where money troubles aren’t part of the plot.
When I do read a billionaire romance, I’m a little fussy when it comes to how they have made their money.
I’m not interested in family money or in people who have made their millions and billions by treating others badly (if you’re a billionaire, you can afford to pay more than minimum wage).
I prefer stories where the person has made their money honestly and without subjugating others, which is why I prefer sportspeople or (even better) tech billionaires. Tech billionaires are also good because it’s more believable that they make their money relatively quickly.
I’m currently reading and enjoying Elizabeth Maddrey’s Billionaire Next Door series about a group of friends who all won big on the stockmarket.