in Trim "everyone" does not mean everyone it means no access control is set. (there is no tsaccess entry for the record / permission) in some cases like for updating records, if modify record access is set to "everyone" only people in the Owner Location group or record administrators can update the record. So if you start chnaging Access Controls from the inbuilt "everyone" to a real location representing everyone you will alter the way that works.
Your question takes me on a nostalgic trip back to the old days when people were upgrading from TRIM Captura to TRIM Context. If they used record type security in Captura, more often than not they had a group in Captura that included all users. When the database was upgraded to TRIM 5.x the "Everyone" group was automatically applied to all the records. From memory this not only made the management of access controls more complex, but it significantly slowed TRIM down, because every single time metadata was retrieved from the database, the query had to include additional access control clauses.
Note: Any posts I make on this forum are my own personal opinion and (unless explicitly stated) do not constitute a formal commitment on behalf of HPE.
(Please state the version of CM you're using in all posts.
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