It means Wild West type Internet rule probably apply---where "anything goes". They likely are in the Internet "frontier" and likely will do what they want and don't care about rules. Perhaps it is run by an eight year old that is judgment proof or a starving college student hoping to be the next Mark Zuckerberg. Sure they can boot you from the forums if they control the code or the WordPress or whatever they use. You should assume they can and will modify, screen, delete or even steal your content. No TOS is a red flag that you are in a WebOfTrust danger zone. Act accordingly.
I am not your lawyer and you are not my client. Free advice here is without recourse and any reliance thereupon is at your sole risk. This is done without compensation as a free public service. I am licensed in IL, MO, TX and I am a Reg. Pat. Atty. so advice in any other jurisdiction is strictly general advice and should be confirmed with an attorney licensed in that jurisdiction.
The basic rules of property law apply -- it's their website, and they can do with it pretty much as they like. They can certainly refuse to publish your content, and delete if if they want. They can certainly screen what you want to post, and they can boot you from the forums. Modifying what you wrote might be tricky, if they change the substance of the message and the changed message is attributed to you. That will depend on the modification, and whether anyone is injured as a result.
i agree with my colleagues. You have no rights on such a site (unless you are a minor and they know their site is directed to minors or likely to attract minors, where COPPA would apply.)
The above is general legal and business analysis. It is not "legal advice" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in California. See also avvo.com terms and conditions item 9, incorporated as if it was reprinted here.
Stay away. Or ask them to see their "terms of service," you were unable to find them on the site. That will flush them out. I would not feel comfortable spending time on a website that didn't even pay lip service to the terms and conditions of use.
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