I may not always (or never) be right at the front but I wouldn’t say 95% are, or should likely be, putting out steady power. There will still be climbs, there will still be wind, and, there will still be a bit of fight to stay in a group and stay in the draft. You’re likely not putting out the spikes of the first group but ticking out a steady wattage for 100+ miles, for me, would be pretty boring. I still like to race a bit. Even in the back.
All depends what you are looking for and what you’re looking to get out of it. Just finish…steady as she goes…do some racing for the best placing…kick out the jams a bit.