our sub discussion was visible to the whole team. this way room belongs to a team and not a certain topic. we moved to teams and we loved it instantly, we had a separate tab aggregated all the files upload. we won't be in worth situation than we are. We was paying for office 365 and thought why not give the teams a shot. if someone forget to check the checkbox to post the subdiscussion in the main discussion thread, other team members even won't notice such discussion is in progress.
also the slack UI for sub discussion is very stupid. you will end up with a tons of not-in-use rooms that you don't want to clean up them for history purposes. each time for a new subject that you wanted to discuss, you needed to add all the team members into a new room. On mobile there were many cases that I didn't get notification of important discussions. and more annoying whenever you search, it opens a webpage and doesn't do it in the app. the search ability was useless in free tier. after a while we hit the slack free limitation quota. We were using slack and at the same time we had a subscription with office 365. Skype has a broader approval, being mentioned in 737 company stacks & 735 developers stacks compared to Microsoft Teams, which is listed in 47 company stacks and 33 developer stacks. Typeform, Starbucks, and PedidosYa are some of the popular companies that use Skype, whereas Microsoft Teams is used by Macy's, Heimdal Security, and Sainsburys. "Free" is the top reason why over 4 developers like Microsoft Teams, while over 248 developers mention "Free, widespread" as the leading cause for choosing Skype.