private void updateTimestamp() {
    if (
      getSettings() instanceof ProjectViewSettings projectViewSettings &&
      projectViewSettings.getSortKey() != NodeSortKey.BY_TIME_DESCENDING &&
      projectViewSettings.getSortKey() != NodeSortKey.BY_TIME_ASCENDING
    ) {
      timestamp = 0; // skip for performance reasons
      return;
    }
    var timestamp = getFileTimestamp(getVirtualFileForNodeOrItsPSI(this));
    this.timestamp = timestamp == null ? 0 : timestamp;
  }
private void updateTimestamp()