I would never have noticed the cowbell in the original song, it's mixed so quietly. Now it's all I can hear.
And every other song with the least hint of cowbell, as well.
You just need to "explore the space".
I have to admit, I probably can't hear that song now and not notice the beat of the cowbell in the background.
I saw Blue Öyster Cult in 2020. The lead singer/guitarist's mother in law had recently died, and they dedicated their performance of Fear the Reaper to her memory.