These are two opinions that often come up when a career in film/tv music is being discussed: 1) anyone can do it. You just need to work hard and persevere, then everything is possible 2) it's impossible to earn a living in that business. There are way too many composers, many of them work for free to try to make the cut. And no matter how talented you are, luck is the only deciding factor. There is only a small handful of very lucky people who actually make it. The rest is epically screwed.
My experience in this field is extremely limited. So I am probably a terrible person to give advice in that regard. Take my ramble below with a large pinch of salt, then.
Anyway, from my limited experience, both views are wrong, and both are right. Depending on what you are actually talking about.
View 2) is talking about becoming a super reach and famous a-list hollywood composer, or a rich game and tv composer. That's unlikely to happen no matter what you do, very true. (Still I'd argue that skill plays a role in that as well, not luck alone).
1) is talking about earning a decent living as a composer/musician. If you are creative, and not dead set about working exclusively on films/games, your chances of earning a decent living wage are not that bad. You can arrange, do the mockup services Chris mentions in his video, gig if you are an instrumentalist, teach, write production music.
I don't know enough about the industry to tell how hard it is to make a living from it. From my own experience, I am working in the classical music biz, earning my living from that. As a hobby I have written production music. That music has aired on tv stations all around the world. I enjoyed creating it. I am happy that it is being used and sells well. It brings in some money on the side too. I have not produced anywhere near enough music to earn a sustainable income from it. But if I take it as an indicator, it seems possible to me if I had more time to invest in it.
Now it depends on how you look at it. You could say that I failed as a tv composer. No single person on earth would recognise any music from me, or has ever heard my name as a composer. Ok, my girlfriend and my parents do. But I suspect that they are slightly biased. On the other hand, millions of people (it's no exaggeration, it's really millions) have heard music that I have written subconsciously, as a background in the tv programs they were watching. And I am just one guy creating music at his computer as a hobby. To me that is mind-boggling.
Anyway, that's my experience with creating production music, for whatever it is worth.