I was so glad recently to see someone tossed out of an lds discussion group who was clearly insincere. Thank goodness. I wish I would see it 10 times more often. If we have been ordained deacons then we have a priesthood obligation to ensure the doctrine is pure.
Christ spoke many things in small groups -- he didn't just post a notice on the front door saying "all are welcome, come as you are". Think of the times Christ had a public discussion, and then said more when he was just with his disciples. Christ met for the passover in an upper room with just the twelve.
The priesthood obligation to keep the doctrine pure includes keeping the pulpit restrained to those who are sincere. And that includes in forums that we ourselves are in charge of because one of us created them.
When someone is insincere, and especially if they are spouting apostasy and dissidence in a forum we have created to discuss the gospel then yes, we should toss them out of it.
In my experience, those who are sincere will feel relief to see someone who clearly is insincere go.
We don't need to worry that to gladly do our duty is to somehow be glad that the person being evicted is misbehaving. There is nothing wrong with being happy about right being done. There is no reason to mistake that for being happy that the person themselves is corrupt. When right is done, the souls sighs with relief. It makes people happy.
Assuming the church obeyed Paul and he got the church to excommunicate the man who had sex with his own mother, don't doubt that Paul's heart was gladdened at the news. That doesn't mean Paul was happy that the man had commited the act. If Paul wrote condemningly to them for not doing so, don't doubt he wrote congratulatorily to them for finally doing it. When those who were rebelling within the church were excommunicated by Alma, don't doubt there was a tremendous amount of gratitude. But no one was being grateful that anyone was being wicked.
It drives away the Holy Ghost and makes it impossible for all to be edified and rejoice together when someone is being insincere and particularly if they are spouting apostasy and attacking the doctrine in the middle of the conversation. Of course people are happy when the impediments to such joy are removed. It doesn't mean they are happy that people are apostate.