Airplane Etiquette Question

So I was on a recent flight where I had the window seat, and the person in the aisle asked me to close the shade because it was too bright for them. I didn’t mind either way, but it got me thinking — what’s the etiquette here?

If you’re sitting by the window, do you have the “rights” to decide whether the shade stays open or closed since you chose that seat? Or is it reasonable for aisle/middle seat passengers to request you to close (or open) for their comfort?

Curious what others think — is there an unspoken rule here, or is it just a matter of compromise and being polite?

Has this happened to anyone before?