I try to run YouTube in librewolf with adblockers stacked to the tits but every so often I have to use Chrome. The volume of gambling ads is repugnant.
It probably depends on the algorithm. I never see gambling ads on YouTube.
Also country. Visited Sweden recently, gambling ads everyone on the internet, on TV and in public spaces, but back home Spain I still see some, but nowhere near the level as it was in Sweden.