This is not an intuitive icon or button to have for a play queue. I have no recollection of any mp3 player interface or streaming service that has ever had a treasure hunt ensue to see what you are playing.
It should be available under view in the task bar or it should be under Main on the left bar. Seriously Spotify who does your usability studies??
You didn't realise she was a female but assumed she was and claimed it was a sexist statement. That's a perfect storm of virtue signalling and group think right there.
And your passive agressive statement actually had nothing to do with sacrcasm. It was a direct and false claim that someone, who's gender YOU assumed, was being sexist, even though it was in reference to hair colour. You're right that a 'blonde moment' has some sexist overtones but it's more 'genetist' and also relevant whether it's a male or female, which you didn't know when you made the comment.