Re: Teams vs. Slack
Unfortunately the education version straight jackets you in certain ways, meaning it's a collaboration tool focussed on educating and teaching rather than education, administration, research, business activity etc.
For example, at least at the start of 2020 individual users on education couldn't create their own custom sidebar of shortcuts - after a few hours it would revert and insist on you having Classes taking up one of the vital 6 spots there, even if you were an administrator working in student records or a manager for in-house facilities like cleaning and maintenance where you would find, say, Shifts a more useful application to shortcut.
Biting the hand that feeds IT
