I enjoyed this film a lot. Watched it in a cinema when it came out and watched it again on a streaming service.
The scene when Jack visited "John from Liverpool" in no man's land and hugged him saying "you made it!" was beautifl.

If I landed in a same situation as Jack? I would sing Wonderwall for every single person I come across but no way that I would make a fortune of it because I can't even play a guitar.

It's a feel good film isn't it, nothing too complex and straight to the heart sentimentality. I really liked it.

Interestingly, the questions you ask in bold made up a bulk of the original script for Yesterday before it was omitted when turned into a mainstream, feel good film. It's a fascinating debate. Although the quality of the songs would always be undeniable, the timing of the release of these songs, the culture they are released into and obviously who performs it definitely helps with their popularity.

I've also got this almost cosmic theory that the human mindset can subconsciously tell the sincerity and authenticity of a song and if its being delivered by its authors. You could get better musicians or better singers to sing those Oasis songs but it just wouldn't have that raw characteristics that are recognisably human. It's another downside of chart music that's mostly made up of songs written by committee. At best, many of these are infectious and very catchy, but they don't have that visceral power that a raw tune like Live Forever has. Something is lost in the process when there's no direct line from creator to performer. I think we have a natural predisposition to appreciate the rougher edges to musical performance too, and smoothing them out disrupts that raw, passionate energy.

Okay, classical music is maybe different - it's perfectly performed, nothing is 'raw' and its being performed long after its composer has died, although they are in many ways directly channelling the art of the creator by identically following the original composition. The rules are literally laid out by its creator note by note to be meticulously followed in a way that works differently from the more spontaneous pop music.