Accurate is an exaggerated definition, let's say with a good dose of accuracy, but never correctly.
In games, everything can change in a matter of seconds; a mistake or a wonderful play is enough to completely change the outcome of the game.
It still manages to give a good chance of guessing the outcome, but I wouldn't call it reliable.
AI accuracy is really an exaggeration when we are talking about sports bet because we are dealing with humans that have errors. AI can predict perfectly based on past performances of a player or team and it'll give it's analysis based on past statistics but a team or player can make a mistake that will alter the perfect analysis. Whether it's humans or AI predictions of sports bet it doesn't guarantee wins what every gambler needs basically to win is luck. If AI is helping a lot of gamblers to win I don't think that casinos can survive, they will all gradually shutdown because they'll all go bankrupt.