Meanings of increasingly thin in English

Schoolchildren are prosecuted for making fun of a president who appears increasingly thin-skinned.

However, soils on steep hillsides become increasingly thin and fragile with increasing slope.

But his charm is wearing increasingly thin and his responses are less and less plausible.

David has been the leader of the group for three years but allies are increasingly thin on the ground and the junior males are restless.

But as this second series kicked off, I realised they are actually the same laughs repeated again and again, which makes the jokes increasingly thin.