What you failed to note, and which is actually relevant, is that developers can opt out of Steam's DRM altogether, in which case you don't need to have it running in order to launch the game. Which still leaves the burden of downloading, accepting and installing Steam, but at least it's much better than when they don't opt out of it. However, there are very few games like that, and the fact that they don't use Steam's DRM is usually not advertised anywhere, so there is no way to tell if it does use it or not.
As for investors, there is a clear case for no DRM, the developers just have to present it right. The facts are out there. And if they still don't agree, they are obviously poor investors to begin with.