ROBLOX has no need to make their own editor that would be extremely underdeveloped and aggravating to use. Roblox Studio>Part>Insert object>Texture>rbxgameasset://nameOfFile.png You even get a handy dropdown menu. Upload to game tab in studio via Add Image or Add multiple images You’re forgetting that it’s also easier to upload right now than you stated.
Waiting for it to be moderated is not a step because you can use it prior to it being approved/disapproved. Surely Roblox can and should make this an easier process? Roblox Studio>Part>Insert object>Texture>Paste Assest ID I think what I am trying to get at is an easier way for newer users to create and use textures.