MPV has a really nice feature where it can stream video data directly from YouTube. What did I do? I decided to make a script to play YouTube videos for me.
Doing this is simple enough: mpv '<YouTube link>'. However, you can also specify a resolution using --ytdl-format: "bestvideo[ext=mp4][height<=?<res>]+bestaudio[ext=mp4]" where <res> is the desired resolution. This is a lot to type, so I implemented dmenu and some choices for resolutions: 1080, 720 and 480.
This was just a simple tip from me for you to not use the laggy browser version. I found this really useful for watching videos on older hardware. Combine it with newsboat and you have a really good alternative to browsing YouTube!