1/ It says on the tin "prevents segfaults". It does not prevent segfaults in all cases, but OK, let's debate the other claim.
2/ It also says "guarantees thread safety". What is the Wikipedia definition of thread safety? It varies, so let's take the most common "freedom from race conditions."
Steve come and say Rust can have race conditions https://news.ycombinator.com/item?id=13376485 and that it's a common misunderstanding to think it prevents race conditions. Surely it would be great if the frontpage would not promote it!
Ergo the frontpage claim is false.