In my experience, most pomo thinking revolve around the idea that language is both very important in terms of understanding the world and that language is somehow ill-defined or not objectively definable.. In my opinion this misses the very simple observation that language easily allows us to communicate complex ideas with high fidelity and this type of common-sense view of language has been and remains important to understand the world -- both if you are a 6 year old or a scientist.
Sure, pomo allows a certain way to talk about language and a certain standard for what constitute "proper" use of language and definitions that allows us to undercut language as a useful tool. Using this way of thinking one can then go on to prove (within the assumptions of pomo) that 1+2 might be 54 and the sun is flat or that a banana is worth the same as Microsoft. I suppose that might count as some sort of accomplishment, but so what? how does this make us any smarter? How can this be used to anything useful?
A person might say this way of thinking about language gives him or her satisfaction, that the idea that one can think up a way in which one can say that ones sockdrawer might be the gateway to Narnia is a deeply satisfying experience, but to me this is just undercutting the utility of language. Having a conversation on those premises reminds me of Ray McCooney
https://www.youtube.com/watch?v=HMagY_CQopA
Where I think I would really disagree with pomo is that in my experience, people who promote extreme pomo views are not being consistent at all. SBF might say on one thread that we are wrong to say the sun is round, but in the next he is saying all sorts of factual thing about the real world like that the WT taught this or that previously.. the pomo standard of no objective truth is not as I see it being applied evenly at all and this does not seem honest. Pomo is more like something that get's pulled out on occasion to annoy Cofty or other scientifically minded people and when the job is done we are right back at using words with their usual meaning (apples are round, pizzas a circular and drain cleaner is not a kind of gravy); often this derision of ordinary language and it's use can happen simultaneous on two different threads which just seem bizarre.
I suspect this is true of most pomo writers who believe that all sorts of questions have objective answers when it suits them (what is my salary at the university? Is my spouse seeing someone else? did the mechanic repair my car? is my child ill?).