Jetpack comments will replace the PLM comments. So you cannot use both at the same time on one domain.
You are now able to create Learning Channels that are open and no longer required a membership to be attached to them!
To create a free content displaying learning channel tab on a learner profile, follow these steps:
Navigate to eLearn Commerce -> Personalize Learning to create a new channel or manage an existing one.
To create a new channel, click the Add Learning Channel button on the top left side.
Give your channel a name.
In General Settings, under Access Rules select the Open (Free) option from the drop-down.
Continue editing your channel to set it up and add content. Once you are ready, click Publish!
There is a Walkthrough for this!
Learn how to set up a Learning Channel for 1:1 or Group Conversations!