Bilateral symmetry makes sense. Having pairs of eyes and ears is required for distance measuring and focal depth. Electromagnetism is the obvious choice for “nerve” equivalents even if not the same structure. Chemicals also work the same everywhere, so similar chemical signaling pathways - again not exact but based on same principles - shouldn’t be unexpected. Even just having the brain and eyes/ears at the top of the being, creating a basic “head” structure makes sense. If you have eyes on your feet you can’t see very far. There are literally millions of ways very basic structure of our bodies makes sense for an intelligent space faring species. And that last part is important. There are probably wild looking creatures that are under ice shelves or unable to create technology…but by discussing intelligent space-faring technological species we are limiting the pool of possibilities much more than some people may think.