I have a 16-year-old son. I’m in my early 30s (had him very young) and a professional footballer. My son also dreams of becoming a successful footballer (he’s been playing since he was 6), but he’s just… not great. He’s good, but not great - and in this extremely competitive industry you need to be at least great in order to even stand a chance. So I told him, as someone who’s been doing this for a very, very long time & is active in this sphere, that he should find another, more attainable dream. He took it as me not believing in him, but I’m just objective and realistic.
There’s no way your dad could have known what was going to happen. There’s no way people around you could have known that you were in a career path that wasn’t going to work out well for you. Nobody can guarantee the future like that.
The other thing is that even if you’re working in STEM, to follow up with your example, there are thousands of different jobs that all feel totally different to people working them. It’s quite possible that you could initially hate the field, then make some lateral shift, and find a position that is halfway decent. Here again, nobody knows what’s going to be good for you.
If you want responsible career advice, it’s quite simple. Because there aren’t guarantees, you might want to develop several different skill sets, so that you’re in a better position to deal with unknown future changes. If you think you can learn how to do one simple thing and then have 45 years of happiness doing it, flip a coin and hope luck is on your side.