It seems to me there are three types of people who come to forums like this...
1) Audiophiles who enjoy shopping for equipment and churn through a lot of upgrades. The only way to convince themselves to upgrade is to decide there is room for improvement. As we know, a lot of equipment sounds pretty much the same. So if they want to keep shopping and upgrading, they need to use vague, subjective excuses to replace one DAC with a more expensive one that sounds the same.
2) We sound science types who want to know the nuts and bolts of how digital audio works so we can tweak the last ounce out of our systems. It isn't good enough for us to just want to upgrade, we want to know exactly why it's necessary.
3) People who are in the market for some particular piece of equipment and find the forum from google searching. They aren't looking for flowery descriptions or dense technical explanations, they just want plain language common sense tips from people who know their stuff. Which one should I buy? Why is this one better than the other? Once they get the answers, they go to Amazon and buy it and never think about it again. They do what everyone should be doing- listen to music.
Number 1s are in their own dream world of flowery reviews and compulsive buying. Nothing anyone says can affect them. No point trying. Number 2 people may be interested in theory, but the issues get raised and discussed and then what? Everyone just sits around and waits for a audiophool to come along so it can all be discussed again. Circular. There are a LOT more number 3s than either of the others. They're the ones that appreciate the help. We should be addressing them.