I’ve noticed this for a long time, mostly with country and pop music where staff songwriters at the record label do most of the writing. Strum, tap, strum, tap, lyrics about a waitress getting a big tip, Bill Gates giving money to sick kids for every card sent or email forwarded, or any other internet myth, and hey, you can have an album’s worth of songs done before lunch and be at lunch by 11 drinking a hurricane before you go insane.

Certain melodies and rhythms simply work well for the human ear so hence we hear so many similar sounding songs.

Of course there’s no limit to the potential number of songs since music works mathematically and since numbers are infinite that means the musical variations are infinite.

The simple answer is no. There is always room for a simple Melody or a Love song