HBO Go is the only real clash there (very few people are going to confuse an offering by a well known music site with a programming language or board game). I don't see HBO ever making Go available outside the US so it probably won't be a real issue for many people.
I think the bigger problem with these generic names is that they are hard to search for and crowd the search space. Go is a common enough word that you'll need to search for `"SoundCloud Go"`, since `SoundCloud Go` will bring up a bunch of unrelated stuff about SoundCloud, e.g. "go to your SoundCloud account panel and..." But using quotes will miss sentences like, "SoundCloud has released a new service, Go."
