You do realize that the OP is talking about sports betting. Right? Sports betting isn’t just about luck. I am not just lucky to know that Real Madrid will squash a smaller team. People who do sports betting know when a win will be likely easy and when it’ll be a struggle. Like the match between Barcelona and PSG yesterday, that was the likely outcome because both teams are strong and it was going to be a struggle.
You're right, there are some types of gambling that requires more than luck for an individual to win and sports betting is one of them, asides luck in some games you'll need to be a strategic gambler also follow up some sporting events as well. A person who doesn't watch football or know about the Spanish Laliga might not know that Real Madrid is a very big team in the Laliga and might bet on teams like Mallorca to win against them.
Sometimes luck might play a good role too and you'll see Mallorca defeat Real Madrid maybe due to an error from Madrid's defence but lucks like that doesn't happen often and sometimes it might even take once In five matches for Mallorca to win or draw against Real Madrid. Therefore to be a good bettor in sporting activities you must have a good knowledge about the sports game and the teams you're betting on, instead of depending on luck always.