Why a wire into a value box does nothing

Dragging a field into a number param connects, greys the box out, and changes nothing. That is not a bug in your graph. Most nodes read a plain number for a param and never look at the field behind it.

Two kinds of param can take a field.

A per-instance param, on Transform, Color Ramp, Set Material and Instance on Points. Wire a field here and every instance gets its own value.

A per-element mask rail, where the field chooses or scales what an operation does to each vertex, face or point. The rails are listed below, and they split into two kinds: a magnitude rail uses the field's value, so elements come out different from one another, while a binary rail only asks whether the value cleared a threshold and then applies the same setting to everything selected. If you want lumps of different sizes, you need a magnitude rail.

Anywhere else, use a knob. A field into Bevel's Width, Set Position's Strength or Subdivision's Iterations connects and does nothing. For masked subdivision, reach for Refine instead.