The data is not centralized in the same way, making it slightly better, but yeah. A lot of the same pitfalls of centralization happen there. The whole system doesn't operate without the corporate servers in the middle, even though they don't see or store the data. They have total access to Metadata. The organization could be sold for profit, shut down, change terms, etc.

If security is important, you're better off with something decentralized like matrix. I'm not an expert, so hopefully, a lot of people here who are smarter than me will fact check these statements, but at least those are my impressions.