I can predict i will die when im older. Your point is foolish at best.
It is possible to have predictions that are based on solid logic. Such as when I posted that the S&P would return to at least 3100 shortly (I think I posted this back in April) and it only took 2 months to happen.
I can predict that if corona vaccines are effective and distributed in mass, that economies will improve. I cannot predict how much the shutdown affected things in the longer-term.
Even if a prediction isn't with 100% certainty, then I can still say something should probably happen, meaning that it has a >50% chance of happening (or even 70%-90%).