Their terms are focused on the transcoding of Plex and other video servers, not chat apps. You won’t get in trouble for using Talk. [They] do this because of overselling their servers. Agreed this T&C is totally stupid.
Main issue with this provider is that their servers heavily oversold (slow) and they do not offer any sort of dedicated resources. Also, the only help they offer is via tickets, which take a day for a response.
If all of that sounds fine, they are super cheap. I recommend them for running a lot of small services, but expect bare minimum everything.