I think today is a minimum requirement for any basic education level. If for reasons of age or country language political context, don' have it and want to leave your small local parcel, learn it's mandatory. Today it is easier than ever.
My first language is not English, but I develop a little reading and writing. I know that my expression isn't perfect and possibly for a native english is annoying my fault and my absurd mixed past, present and future in the same sentence. Also usually, due google translate, I use perfect words and expressions in english but are not common. I always appreciate the patience of who answers me.
The only gap that I have is with the videos, listening is a big problem for me no matter how hard I try, I can't follow details and for example irony is my big handicap.
I believe that a very effective cost/benefit solution, even help people with hearing problems or unfriendly circumstances for audio, such as public transport without headphones (I always forget them), it would simply subtitled (english of course) Dave videos. Youtube automatic translate for Dave videos it's a joke.
Try to build their PSU, only listening the automatic subtitles
(icon for explosions?)