Conversations among multiple participants for collaboration and communication in Teams
Good day! I'm Raniel, a Microsoft user like you. I understand your frustration regarding this issue and I'll do my best to help.
It appears that the option to block someone is only available for Microsoft Teams personal and Microsoft Teams small business. Please see this article for details: https://support.microsoft.com/en-us/office/bloc...
I suggest that you submit this as a feedback using this link: https://feedbackportal.microsoft.com/feedback
Here is the article for your reference: https://support.microsoft.com/en-us/office/user...
I hope this helps. Good luck!