What’s your use case? Likeminded techie friends? Family members?
Signal works well as an alternative to the likes of Telegram and WhatsApp, even if it still requires a phone number and is centralised. Far easier to explain to the family instead of “oh well you can sign up on this website or this website or that website”.
Granted, if you want to host a small Matrix server just for the family, then go for it.
They’re Ryzen processors with “AI” accelerators, so an LLM can definitely run on hardware on one of those. Other options are available, like lower powered ARM chipsets (RK3588-based boards) with accelerators that might have half the performance but are far cheaper to run, should be enough for a basic LLM.