Yes, it's still worth getting into a saturated niche.
I don't really start threads here to give advice because it's all so nuanced. The same tip can be great or awful, depending on circumstances.
But I think one thing worth shining a little light on is the idea that a saturated niche might be too crowded for a newtuber to get started in to have any hopes of doing well in it.
This often gets right down to the root as to why a lot of channels might struggle.
The reality is stupidly simple: A channel will struggle in a niche that is saturated when you're doing exactly the same thing as everyone else in it. But if you can add an element people really enjoy that only you (or very few other creators) can provide, a saturated niche stops being a hurdle and actually becomes a huge advantage. You're now standing out in front of a massive audience, which is VERY different than doing something so unique that you stand out for something few people are doing, but the audience for it is very small or unproven.
So it's not just "do something different".
It's do something different in a sphere that already has a lot of interest. A saturated niche is the easiest way to do that.