Why do not transverse waves appear in liquid and gaseous media?

In different states, different physical processes arise in substances, for example, waves. But the waves may differ depending on the state of aggregation of matter.

Types of aggregate states of matter
A substance can be in different states, such as:

Liquid state;
Gaseous state;
Solid state;
Plasma.
The liquid state is the middle, the gap between the other two states. A substance in a liquid state has the function of changing its shape under the influence of external factors.

In the gaseous state, the molecules are very mobile and practically unrelated to each other.

The solid state is distinguished by its immobility and the state of thermal motion of atoms in it.

Plasma is an ionized gas in which the particles are, on the contrary, very mobile.

Where waves arise
Waves are of two types: shear and longitudinal. These waves differ in their oscillations: in a longitudinal wave, oscillations go along the direction of the wave’s motion, and in a transverse wave, the displacements of particles are obtained perpendicular to the wave’s motion.

Accordingly, for a shear wave to occur, it is necessary for shear deformation to occur. And this deformation is absent in the gaseous and liquid state of substances.

Shear wave can occur in the solid state and in the plasma state.