Wonder if it can be used to void warranty like the analogue version - https://en.wikipedia.org/wiki/Liquid_contact_indicator in non water resistant phones
They have to prove the water caused the issue, not that a sticker got wet. It's like "warranty void if removed" stickers - not legally enforceable.
https://www.ftc.gov/legal-library/browse/statutes/magnuson-m...
https://en.wikipedia.org/wiki/Magnuson%E2%80%93Moss_Warranty...