Is this a known thing? I'm convinced it's the case, especially for emails from the 2000s. My email usage dropped in the 2010s, so I don't have as much important

Is this a known thing? I'm convinced it's the case, especially for emails from the 2000s. My email usage dropped in the 2010s, so I don't have as much important stuff stored in there, but there are periods of my Inbox history, where I know I was using Gmail heavily, that have basically little more than a handful of emails anymore.