However, while there may be a few different instrumental songs that have done well in the 21st Century, only one of those ...

Jeff Beck released this instrumental track on his 1974 solo album, Blow by Blow. The album itself was an entirely instrumental offering and it was popular, hitting No. 4 on the Billboard Top 200.

10 "Buckaroo" From 'The Instrumental Hits of Buck Owens and His Buckaroos' (1965) Coming in at just over two minutes long, this 1965 Buck Owens and the Buckaroos song was the fourth No. 1 song for ...

But an exact comparison is best appreciated by recapping all the Top 10 instrumentals in the U.S., for the 520 weeks that were the 1960s. Those numbers clearly support your belief.