BroadcastPreGarbageCollect in my case is related to flushing the async loading pipeline. This depends on the content referenced by the loaded level. Skipping the WP initialization can help if there aren’t many assets being loaded asynchronously based on what you report.
I have created an internal ticket for the Editor team to review the situation. It’s unclear to me why opening an asset through the content browser pre-load the package. It might just be a case of adding an exception in the case of a WP level.