As an example, I play accordion and I like to hear other accordion play songs on YouTube. There may be lots of covers of a popular song I want to learn, but there are rarely many accordion covers, let alone good ones.
So the question is whether you are looking for generic entertainment, or do you take an interest in something specific? Add another search term to a query and the results can thin out pretty quick.
From a professional creator’s point of view (not me), the question is whether these niches have enough money in them to get started and grow from there? And that depends on market conditions. Can people find what they like when it’s not mainstream?