You are disregarding that the bullet text inscriptions are common alt-right memes? That the suspected killer is from a conservative family upbringing?

Or you don't believe those inscriptions have nothing to do with the alt-right movements? That the conservative family is also to be disregarded?

Now about more evidence of participation of the killer in alt-right movements, or other links, you can be damn sure the current US administration is not really intereesting in making any of that public anymore, since it goes against the current administration propaganda. If it was some "leftist" you can be damn sure there would be a deep investigation into the killers electronics, internet activity, and etc, to find other "leftists" and politicians to associate with him and ALL that would be publicized by Donald Trump himself.