Google usually treats these non-critical pages separately as long as it is viewed as a completely different content type. For example, an e-commerce site with Products should not have to worry about slow “Manuals” pages affecting their sales.
Plus, Google’s crawler and testing tend to focus on the most popular pages since it has limited resources. That means those non-critical pages might not even undergo the core vitals testing.
“…for the most part, the things that we will look at the most are really the pages that get the most visits.
John Mueller, Google Search Console
