All waterproofs keep water in, aka sweat. When they talk about breathable they mean in vapour form. Once water has condensed out the air, or sweat on the skin it has nowhere to go. The high humidity that waterproofs cause within leads to a lot of vapour condensing out the air, and once liquid it’s not going anywhere due to that waterproof barrier. You’ll often end up wetter than the amount of rain that could have got in.
If you wear work clothes during commute then get a cape. If you don’t wear work clothes during commute then get a base, insulation, and outer windproof layer that’ll keep you more comfortable than a waterproof and no wetter, and often drier in reality as liquid water and sweat can get out and away from the inner layers. Your skin does not care about moisture in outer layers.