> The ecosystem is vibrant, healthy, and will keep growing.

I'm in favour of it, and hope it does well. But at the same time, constant growth itself doesn't mean that much.

There's a big difference between slow constant growth and explosive constant growth. Something can constantly grow yet still remain something most people have never heard of. I think Linux on the desktop is a reasonable example of this.

The alternatives will likely be constantly growing as well.

> in my mind there will eventually be a tipping point

it's going to be difficult to compete against YouTube... there has to be some reason why people use it instead of YouTube.