The process of making and selling an information product is a relatively simple one. There is no great complexity involved.
True-you will have to learn some basic skills. But those skills can easily be acquired from freely available online sources such as YouTube. There is almost certainty no skills that cannot be learned from a YouTube video.
So, if the process is simple, and the skills can be easily picked up from online resources why do more persons not do it? Why do they not sell their own information?
Probably for the same reasons that so many people are employees as opposed to being self-employed. No matter how big or small your business becomes there is a massive difference between the employed and self-employed status.
Being employed is comfortable and safe, most of the time. Being self-employed, and starting your own business from scratch, is much more uncertain. More of a white-knuckle ride, with no guarantee of success.
This should not stop you if you have this ambition.
If you want to do it, you can. But you will need to buy into the process of trial and error, hard work, trying and failing and trying again, iterating and repeating, and so forth.
You may also be interested in starting a side hustle in the knowledge business and selling your information product and building a following.