Absolutely not! In fact, there's never been a better time to get on. YouTube is seeing an increase in it's viewers every single year with more and more people piling onto the platform. The beautiful thing is that the framework laid out for you in YT Platinum allows you to leverage these things to your favor!
Even very saturated niches can still work well in your favor due to the ever growing audience, and their constant need to consume new and interesting content. It leaves so much room for newer content creators to break through. Not to mention you being able to pop up in very popular videos in that niche and break through ;)
Remember that competition is a good thing, and it doesn't work the way you think. In a traditional sense, competition really means you vs. them. But in YouTube, 99% of viewers end their viewing experience on a video or channel and want more, so they might stumble onto your videos. They're never satisfied. This is the beauty of YouTube and why I personally disbelieve that there will ever be 'too much' competition.