It just that this is not about influencing other people but more about privacy, by maintaining the privacy of every gambling result, we can indirectly avoid various negative actions that could occur.
In many cases, such as hacking, extortion and robbery, by showing the victory we have obtained, it means we have allowed or invited bad things like that to ourselves.
So basically all of this is not just about being affected or not but more about our own security.
Moreover, I sure that only few gamblers will talk about or share their winnings publicly and most will always keep it secret.
It's better to keep your gambling activities a secret, I myself keep it a secret, because I don't want conflicts with each other. Apart from that, in my opinion, sharing your victory or defeat with the public will not be beneficial, maybe for people who like to show off they will share their winnings with the public, but it seems impossible for them to share their defeats with the public.