Maybe it looks identical on the surface but seems like you haven't actually compared it by using it or looking at the features list on the site. I wanted to move away from using YouTube in the browser but wasn't satisfied with FreeTube as it missed a lot of power-user features I have previously used extensions and userscripts for. To one of my feature-requests (channel-specific playback speed) they just said it's "too niche" (as they do with a lot of them) what brought me to starting the project.

But it isn't based on Invideous, which fails too often to load the Video, because YT actively block it. This client use another system and apart I put the SMplayer as extern Player.