It really is about discoverability, though.
On Youtube, everything is about producing enticing videos and if you do a great job, the algo will favor you even if you are a small channel. Youtube search plays an important part in all of this.
On Twitch, the unit of interest is the live stream and that is much more difficult to produce content around. It also makes finding interesting streams challenging because search doesn't work well with this type of content. Heck, you can't even query the directory for basic stuff like [show me streamers living in Sweden who usually stream GTA 5 RP].