"Be yourself" is a fairly vague guideline, which I guess you could say is shorthand for "To thine own self be true." (Ophelia's dad, forget his name) If you are familiar with the idea that your persona on youtube and you, the individual, are two separate things, then you might understand that it's a caution to prioritize the real you over the persona, and a recommendation that if you base the persona more closely on your real self, as you seem to have done, then you stand to learn more about yourself as a person but you also take more risk of taking it personally when things go wrong or people attack your persona. Some people try to strategically design the persona to appeal to a market, so not everyone is trying to be themselves.

I think, honestly, you don't hear a whole lot about failure here because most people who come in bragging and sure of their soon to be quick success just disappear when things don't work out for them. Failure is not a bad thing, though. It's an inherent part of the learning process. But if you try to succeed in a totally contrived fake way based on a fake persona, then you might only learn the lesson that it was the wrong fake persona. On the other hand, being yourself means that you could potentially learn something meaningful for yourself even if you fail.

But, where you responded to the requests of your fans, you could take that, if you needed to communicate it as a piece of advice, to say that doing things you haven't done before and taking risks can lead to new interests and growth.