The column names in the data table editor appear to directly use the property name instead of the "pretty" version of the property name. If the "DisplayName" meta specifier is used, though, that is respected.
Versions tested (issue occurs in all versions):
4.19.2 - CL 4033788
4.20.3 - CL 4369336
4.21 Preview 2 - CL 4489857
Result: The table column names are displayed using the property names. ("bSomeProperty")
Expected result: The column names should use the "pretty" names of the properties. ("Some Property")
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-66108 in the post.