The person you're responding to isn't even talking about the cut. It's the threshold at which you may take money out of the ecosystem. Both YouTube and Roblox take a cut, but with Roblox, even after the cut, you need to have made a substantial amount of money before you can see a penny of it.
I’m not sure why anyone would defend a dollar amount above $1. If you have money in you should be able to get it out immediately IMO.
To be honest, when I think about it that way, you're not going to get that far under $1000 no matter what you do. There's tax forms at the very least, and probably extra stuff to do with dealing with minors, plus generalized legal risk of being sued or investigated anyhow... we need to be dealing with more than a few bucks here before it's worth Roblox's time & risk. Some of this is the cost of protecting minors, too.
YT probably does need to exist for many creators to get the kind of distribution that enables them to monetize their content including the operationally managing the scale of the site, the brand they've built and the ad network. A highly viewed piece of content is generally much more valuable than unseen content. Which isn't to say you can't monetize video outside of YT, just the YT is providing a very valuable service and it isn't clear to me that is qualitatively of less value than what Roblox provides its content creators.
In reality the relationship between these platforms and the creators is a necessary and mutually beneficial relationship. The exchange in value between these parties should be in a format useful to both sides: cash.
When you make a video and upload it to YouTube, that creation is entirely the result of your own hard work and ingenuity. YouTube doesn't need to exist for your video to exist.
When you make a game in Roblox, you are combining some amount of hard work and ingenuity of your own with a larger amount of hard work and ingenuity by Roblox Creation.
If you want to keep all the money, then you need to do all of the work.