Simply put, it is impossible to become an expert on Bitcoin. Because we talk speculatively about Bitcoin. It's not just us common people who invest small amounts in Bitcoin. There are many institutional investments and there are many large whales. They can change the price of Bitcoin anytime they want. Therefore, it is not possible to predict the future value of Bitcoin, only speculation.
How is this not possible? Open any specialized publication or media and it will be full of such experts. Also, don’t forget about the bloggers on YouTube, of whom there are already hundreds and someone considers them experts (including themselves). The second question is about their competence and how professional and correct they are in their forecasts, but how do we know how many people have so many opinions.
Do they have proven experts? No, but they just proclaim themselves as an expert. In fact, nobody could be an expert in speculation because no matter how these people do, they can't predict the market. They are professional but it doesn't mean that they are expert in speculating the prize because nobody makes it right. And what they did is just their own opinion and of course, that could be based on the market history.
And you are talking about YouTube bloggers? Most of them have no deep knowledge of crypto, they just pretending.
We can speculate the trend of Bitcoin but if we think being an expert, that is impossible.