If your data has a texture with transparent RGBA colors, or a vertex attribute with transparent RGBA colors, or if you have
colorExpression that results in transparent colors, you can use
TileSet3DLayer.transparency to make sure that the transparency is picked up.
Activating transparency can affect performance, so it’s disabled by default. When it’s disabled, the alpha value of colors is ignored, resulting in opaque colors instead.
Note that points within a point cloud typically overlap a lot. The color values of all points on a pixel are blended together. Depending on your data density and point size, the result can be an almost fully opaque pixel.