Contribution date no longer has a time on the form
https://chat.civicrm.org/civicrm/pl/sgxqjrxq6pyaxftxftwtexf56a
The field itself still stores a time, but it's the "current" time which may or may not make sense.
If I remove this line it comes back: https://github.com/civicrm/civicrm-core/blob/9eaef13ef15da8bac6b73148d570fd989529789d/CRM/Utils/Date.php#L1990
Seems to be from https://github.com/civicrm/civicrm-core/pull/27003, so works in 5.65 but not 5.66.
Also receipt date, so it probably affects any date field that isn't somehow specified as TIMESTAMP. I'm not sure where it gets that "metadata" and whether datetime and timestamp here mean the same thing as they do for db fields.