Giving more publicity to these people and their ideas is sometimes what pushes people to do things like this in the first place, so cutting down on the spread of that sort of information could help minimize future occurrences. That being said, I doubt Reddit is being so benevolent as for that to be their reason, they probably just don't want the possibility of bad press.
Note that the shooter may be named Aiden, not Audrey - I have yet to find a news source explicitly stating which is their legal name as opposed to the other. This can make it frustrating to find articles about the shooting, so I recommend just using "Hale".
The evidence seems pretty damning from what I've read. Confirmed authentic by Nashville police, too. Big tech and the media seem to be scrambling to cover up and censor the manifesto story as quickly as possible. Make of that what you will... but if this were a right wing terrorist, it'd be news the world over, and nobody would have had an issue with it. The writings shown in the leaks make it very clear that the shootings were racially-motivated - and had been planned for months.
Do you have a link to the manifesto? I can't seem to find it anywhere. It's strange how little information is easily available on it; every article I see in search results is informationless fluff, with various attempts to spin something, but they're all so unclear on what the thing they're spinning is in the first place it comes across very strange.
To be honest I've always kinda thought how much things get censored is overblown, but damn, someone just killed half a dozen people (half of them children), injured hundreds more, and released a manifesto as to why they did it - yet somehow it gets buried. Instead there's an endless stream of speculation, blame, and talk about everything else. I don't think there could be anything in the writing that would concern me more than the degree to which it seems to be deliberately ignored.
For the record, I think the guy is a massive fucking dickhead, but he originally broke the story, and imo, did the right thing here. His Twitter is a good place to start: https://nitter.net/scrowder