I agree with you. In general, European hotels offer a good selection on buffets. Maybe not always complete with missing salmon or waffles or anything else. IMO, the variety ought to be good enough for anybody.

The Courtyards around Frankfurt offer for example filled pancakes, selection of cereals, selection of quark dishes, muesli, selection of jam, bacon, sausages, hot meatloaf, omelette, salmon, mackerel, selection of sliced sausages and cheese, fruits, bread, Danish pastries, etc.
The difference to the Marriott is the food quality: Quark dishes, muesli or other food is often made by the hotel itself, while cheaper hotels buy more food. Eggs/Omelettes are pre-cooked in cheaper hotels; a cook will do it at request in more luxurious hotels.

My favourite breakfast buffet has
- fresh fruits
- cereals, muesli, quark dishes
- fruit juice without sugar
- salmon
- cheese
- coffee and tea (tea leaf, no tea bags)