The Europe/France workaround suggests the installer's timezone list is rejecting US identifiers before the database step ever runs. If the CLI install uses the same validation, a US zone likely fails there too, so testing it wouldn't tell you much. A safer approach might be to check which timezone value the installer actually writes and whether the server's PHP build recognizes that identifier, since internal PHP timezones changed across versions. Worth confirming that before assuming a back-office change would break tax rules tied to the original setting.
