V-VI-I is a plagal cadence. It's most definitely not classically wrong. Take any old hymn, Bach corale etc if they do a big "Amen" that will be a plagal cadence.

https://www.musictheoryacademy.com/how-to-read-sheet-music/c...

For some reason, people who don't know music theory say things like this about the Beatles because they think because they haven't heard something before it must be new.

That’s just the end of a classic 12-bar blues progression.

I am under impression that almost every progression works as long as you are in the key, am I wrong?

"There are no rules of music, only rules of style" - Arnold Schoenberg, Harmonielehre.