JComments is not maintained anymore since 2018. We will remove this plugin soon as not working on Joomla 3.10.
Integrate JComments in your iCagenda.
You need to install and enable this plugin if you want to have comments in your events.
You can now add the tag {jcomments off} in your event full description, to turn off individually the comments for one event.
This new functionality needs iCagenda 3.6.3 or higher.