This issue was addressed through improved state management. This issue is fixed in watchOS 10.5. A person with physical access to a device may be able to view contact information from the lock screen.
[
{
"vendor": "Apple",
"product": "watchOS",
"versions": [
{
"version": "unspecified",
"status": "affected",
"lessThan": "10.5",
"versionType": "custom"
}
]
}
]