Having spent a day in battle with an Internet Troll I then decided to have a discussion with my lady, to try and understand what is happening. She brings an extra prospective as she was conditioned as a child to be a liberal and at one point was a libetard.
The first thing that came to light is that trolls use loose language in order to avoid being pinned down as to meaning. "There is a link between CO_2 and atmospheric temperatures." This is true but it is not the same as "correlation" or "causation". The more concise language allows us to have an agreement as to meaning, the loose language allows the troll to change the meaning if they are about to be penned down.
The next thing that I observed was that the troll will pick definitions that are non standard. You then have a long discussion, prove your point and then are told "We weren't talking about that definition but this one instead." Example: Taxes are an expense is my statement. The trolls statement is that Taxes are calculated off of profits and the Federal tax return doesn't allow you to count federal taxes as an expense therefore taxes are not an expense. HUH? By picking the very closed definition of "Can be included as an expense on your federal tax return" and ignoring the common understanding and accounting definition the troll is able to wiggle out of acknowledging that taxes are part of the costs of doing business.
Next is the "My opinion is just as good as anybody else's". This trope resonates with the equal out come mindset. No, your opinion is not as good as mine in my area(s) of expertise. If you are sick you go and get opinions. The opinion of your general doctor, your specialist and others in the medical profession are going to be more accurate and better than your mom's or your best friend's opinion.
Your opinion is your opinion but you really have to be able to back your opinion with facts. An opinion back with facts can be discussed and refuted. An opinion that is just an opinion is worthless. And you will never be able to make progress.
Another troll characteristic is to belittle you. They will claim you don't understand, have brain issues, have reading comprehension issues. Anything and everything to avoid admitting that their words are not what they are claiming or that they have said things they have not. This moves back to their inability to admit to facts that are contrary to their opinions.
In general it is a waste of your time to argue with trolls. Call them out. Educate the others that might be reading and then leave the field to the smelly creature. They are not worth your time.
The problem with the online world is you can't size people up naturally as you do in person. We often contend with people who we wouldn't waste a second on if we were in the same room with them.