It's not the same thing. This is just open conversation, what Ann is doing is putting herself out there as some NovoCon leader which is what St. Paul condemns. If she were teaching privately, like nuns do, then there's no problem.
Yes, that's my feeling as well. We're all peers here on a discussion forum, sharing our views and opinions, no different than we might do over a coffee and donuts in the church hall after Mass. To extend that analogy, this would be like having someone get up in the church hall and deliver a talk ... a far different situation, because the individual is posturing as some kind of "thought leader".
Some of it is a bit relative though, and depends on the size of the audience. If I were to put up a blog post about some subject, it still presents as if I'm just posting my opinion. But when you get a large audience following your videos or blogs, it takes on a different aspect, and some of it has to do with the delivery. If two or three Catholics had a podcast in debate format, where people had a discussion or argument about various topics, I think that too would be OK. But when you set yourself up on a platform where you unilaterally broadcast your speeches, there's a different sense about it that's like someone delivering a lecture vs. just having a discussion. I also feel there's a difference between writing and delivering "speeches" (whether audio or video) about various subjects.
It's about whether you're presuming to write with some kind of authority. When you have a +Vigano or a Traditional Catholic bishop talk about a subject, their state and often their tone can convey a sense of speaking with authority, from a legitimate leadership position. Bishops have a certain authority (even if not full ordinary jurisdiction) where they can take that kind of tone, and basically deliver a sermon, and "lecture" people about a subject ... in a manner and tone that a layman or laywoman should never dare to assume.
Here's kindof a hiearchy ...
1) Posting on a Forum -- very egalitarian, low authority (only as good as your argument is) ... unless the poster is a bishop or priest
2) Posting a Blog -- slightly elevated level of authority due to its unilateral nature (vs. being on equal footing with others in the discussion)
3) Podcasting -- slightly higher than blogging because it's oral vs. merely written
4) Videos -- even higher authority, making yourself into a personality with some pretentions of being a "thought leader" due perhaps to the size of your audience
So, basically, the more unilateral it gets, and the more the individual is posturing as if having some elevated authority (even if it's just due to the size of their audience), the more it begins to resemble "teaching" the faithful, which no layman or laywoman should ever presume to do. It has to do with the extent to which you put yourself in an elevated position above others, and have an attitude of "talking down" to those beneath you.