Whilst I agree that misattribtion is a problem, I'm not sure how much big players are at fault. The bigger music publishers have bots crawling the internet for any potential infringement of copyright and I'm sure they are on top of it. Whilst Spotify can be criticised for the meagre payments to artists when a song is streamed, I'm sure they take care to stay on the right side of the law.

After seeing Guest, Rossey's post I googled "Bright Eyes". It came up as "song by Art Garfunkel", However to say a song is "by" someone can mean either the performer or the songwriter. Admittedly this may sometimes cause confusion, but both are correct and in widespread use, and I don't think Google can be criticised for saying it is "by Art Garfunkel".

Google also provides the full lyrics, and there Mike Batt is identified as the writer together with full copyright information.

When I looked for the song on Spotify I found a "credits" link, which identified Art Garfunkel as the artist and Mike Batt as the writer.

Of course this is only one example, but it is one chosen by the OP and both Google and Spotify seem to have attributed it correctly.

There is a much bigger problem with lyrics sites, which are full of inaccuracies and mondegreens, and careless attributions.