It's true that the buffets tend to be generous. Anyone especially concerned about COVID, though, should keep in mind that people spend more time in the breakfast room when there's a huge spread. Most of those rooms were really packed during my recent trip (June 15-August 24 in Norway, Sweden and Finland). I opted out of breakfast if I could for reasons of health and cost, but it often wasn't an option. Having paid for that food, I wasn't inclined to skip breakfast. I emerged COVID-free, but I was surprised to do so.
Being at the breakfast buffet at opening time will usually mean a somewhat less crowded experience if you don't dawdle.