Of course it matters if you have correctly oriented faces. It matters when you render, it matters when you export to another format for other software, it matters when you apply textures, when you change geometry, etc…
Just read the topics in section V-Ray for SketchUp - V-Ray for SketchUp - SketchUp Community
and you’ll see a lot of problems created by reversed faces and not knowing about them.
Just an example: Vray creating a Phantom face on section cut - #5 by AndrewRubySketch