Public messengers are cool, but not for corporate communication. Information security services have always had a lot of problems with them. Correspondence in them is not controlled, strangers can get into chats, and dismissed employees leave with all the information. The probability of phishing - theft of corporate and personal data - is high. Information can be stolen and sold. Well, or just lose by inattention.
There is a positive experience of import substitution in terms of messengers. Domestic solutions are still inferior to Western ones, but they can cover a fairly wide number of tasks and will continue to develop. Many financial market players began to switch to Russian products long before the amendments were made to the legislation. Therefore, you should not be afraid of Federal Law 584 - this is a step towards the development of your own corporate platforms.