@jaffathecake I'd vouch for "Option: Nothing by default, but provide a way to trigger an update" (https://jakearchibald.com/2024/how-should-selectedoption-work/#option-nothing-by-default-but-provide-a-way-to-trigger-an-update). It feels like this would follow an 80:20 rule of being sufficient for 80% of regular usage of the element, and allow the 20% advanced usage of developers who know what they're doing full freedom. Since this is based on just gut feeling of expected usage, this choice could use backing by a developer survey (Do you expect to change an <option> when you use this new element?).
@tomayac good feedback! I wanted to avoid a poll, as I wanted more detailed feedback, and I'm happy to collate it. This is pretty in the weeds and I worry that a poll might invite a lot of "I didn't read or understand the post but I'm going to pick an option anyway"