My hunch is no baking powder. I've made pancakes without baking powder by heavily beating the eggs before gently folding in the other ingredients. Haven't tried this particular recipe.
English pancakes are flat.
0.2l Milk, 2 eggs, 80g flour, 15g butter, 30g sugar, 85g beer. Mix milk, eggs, and everything else except the butter and beer. Melt the butter and mix it in too. Add beer, drink the rest. Then make pancakes.
https://www.lacucinaitaliana.com/recipe/cakes-and-desserts/b...
On new years day (YYYY-1-1) we traditionally make it with champagne