It seems Mathworks have listened and changed the behavior of layerNormalizationLayer in R2023a.:
Starting in R2023a, by default, the layer normalizes sequence data over the channel and spatial dimensions. In previous versions, the software normalizes over all dimensions except for the batch dimension (the spatial, time, and channel dimensions). Normalization over the channel and spatial dimensions is usually better suited for this type of data. To reproduce the previous behavior, set OperationDimension to "batch-excluded".