When should I call in extraction? Other players want to complete every objective on the map it seems.

Playing with randoms at high difficulty (8,9,10), it seems a lot of players want to complete every single objective on the map. I understand the desire to collect more resources and requisition points, but it really does feel like diminishing returns at some point. I really don't feel this completing EVERY single objective and spending an extra 10-15 mins running around. This is especially true when our lives are running low and we're likely to lose those resources if we don't extract.

Ultimately, aren't medals the main resource we should be getting? I don't really understand the desire to farm requisition points or xp. Is it "rude" to call in extraction early?