Musical Therapy, Synesthesia and Yellow Rabbit Holes?

Jaguar Jonze — Rabbit Hole

Yellow rabbit hole?

I heard Billie in an interview say that she had synesthesia, which made me wonder if she picked the colour schemes in her music videos.
Well, Owl BE, Billie Eilish Finishes On-top of the Hottest 100 Ladder?

I watched a music video of Deena Lynch's (AKA Jaguar Jonze) called 'Rabbit Hole' and couldn't help thinking of just how much yellow was used in the video, which reminded me of the opening of Billie's 'Bad Guy' video, when she kicks a hole through a yellow wall and climbs through.
I can't read or play music, and I certainly don't have synesthesia, but I watched a You Tube this week about a NDEr who tells of hearing heavenly music and then becoming a music therapist.

Wellness Music Therapy

I'd like to know what significance the colour yellow has when it comes to music and mood, or whether it's just all in the mind.

I guess we all see the world through different eyes? 
Probably a message there somewhere for me I guess?

Persons who experience grapheme-color synesthesia sometimes report seeing impossible colors when red and green or blue and yellow graphemes appear next to each other in a word or number.