Uhm... your standards for Sci Fi must be quite low and very high for fantasy. That is why.
Most of the time both are just impossible. OR at least not believable.
That is not QUITE what the guy was saying
...
Anyways, this second video may help:
https://www.youtube.com/watch?v=Lg_Lp5bO1U8
In the game you have a lot of quests and contracts. Partially explained by the fact that there is a war going on (that makes monsters much MUCH more active). Still, gameplay reasons.
In the books he often goes around for months on end without ANY job at all. Months.
His "mind power thing" will end up with him dead. Not everyone can be affected by it. Try that on a mage and he IS dead. Or someone with a strong will or who knows at least a bit about how to "defend" themselves from such a thing.
It also cant be used in groups. At all.
In other words, it may works a few times. But only a few. And in a few days, the people he used it on would remember what happened anyway. And get people to kill him. Or report to authority.
Try it on the wrong person? Wont work. In front of many people? Wont work...
Geralt is fairly low power in the universe. The game lets you do some amazing things, but the truth is that Yennefer for example is simply MUCH more powerful than him. She has REAL mind control, reading minds and blowing up castles powers... Almost all named mages are OP.