@Maj. Bill Martin I would say two things:
1) public opinion in the United States is affected not just by big media, or by radio talk shows, but also by tens of millions of everyday conversations, postings on message boards, etc., where citizens discuss these issues. Heck, one of the reasons people post and debate is to try to sway others to their point of view. So if the argument is "what difference does it make", I'd respond "if you believe the words you say cannot possibly make a difference, then why bother saying them?"
Because they're not always intended to make a difference--at least as far as changing minds, which, as you admit, is only one of the reasons people debate politics. I think anyone here who believes they're going to change members' minds in either direction is in the minority. This is the virtual version of sitting on the front porch talking back and forth.
Even if I thought there lurkers who were simple-minded enough to be turned against Trump by simple criticism, I'd say that's on them. It's still important to voice what we think. There should be no qualifications that try to tamp down opinions.
2) Nothing wrong with criticizing politicians. But that should go both ways. There are a ton of elected Democrats who are a much bigger problem, but who effectively get a free pass from alleged conservatives who'd rather spend their efforts attacking Trump.
No one here is giving the left a free pass. It's simply not happening.
For me, Conservatism 101 is: Liberals Suck. We know it, we live it. We've been saying so on the internet & elsewhere for a long time. I can only speak for myself when I say that I don't have unlimited time to post here, and when I do, the
latest Democrat absurdity is just that. I can try to hit every such thread and end up repeating myself so people will still believe I'm a good conservative. But it's not going to happen. Unlike TOS, TBR allows me to talk about the ways in which some of the right has gone off the rails, and I think it's an important conversation to have.