LLMs are great and will get better but we have not seen an open source office suite built by LLMs come online yet, and even if there was one I'm pretty sure few would adopt it, cause that's not the only moat, LibreOffice has been around for decades.
Sure they didn't build it from scratch but what I'm saying is that there's no moats anymore. If you build something, they will tear it down to its composite pieces and assimilate it.