If I find something without particular significance that's not a part of an archaeological site, say a Roman coin in a field somewhere, it's fine if there's a requirement that a museum gets to take records and do any sort of scans it wants. But unless it was some item of particular cultural heritage or research interest, the museum should give it back to me or buy it from me or give me something in return like a fair tax break.

Lots and lots of stuff gets cataloged and archived and basically never looked at again resulting in little archeological value or any other public value and is kind of just scientific hoarding.

I mean roman coins for example are so plentiful that they are sold relatively cheaply, we have more then enough of them for all the museums of the world if they wanted them. I don't think viking era treasure is anywhere close to as common but there comes a point where it's plentiful enough.