I don't think the spirit of the Constitution is being violated here at all. As you say, the Constitution didn't account for private speech making it so easy to

I don't think the spirit of the Constitution is being violated here at all. As you say, the Constitution didn't account for private speech making it so easy to reach a wide audience, so it doesn't really have anything to say here, one way or the other. Personally, I think having a government Twitter as a "digital public square of last resort" is fine as a solution, as long as it has no curation abilities whatsoever: no recommended pages, no default feed or algorithmic timeline, not even a search function. Any pages you get to come via external links, or internal links placed manually by whichever page you're looking at. This way, you avoid any issue of bias, and while there may be Nazi pages somewhere there, you wouldn't be able to get to them except by getting linked elsewhere to Nazis, it wouldn't be the platform actually recommending Nazis to you (because it wouldn't recommend anything).