I'm not sure if the screenshots are showing equivalent requests, as they look very different. Are you sure they're for the same page, and under the same circumstance (e.g. whether you're visiting the page for the first time, or revisiting it) ?
One oddity in the second trace is that requests are repeated, with an HTTP 200 response. You can get repeat requests if the client first tries anonymously, but that'd give different response codes
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