I don't like Wikimedia nor the Wikipedias, but I don't get your point and I think you're incorrect (unless you're talking about Wikipedia's early days).

The way Wikipedia should work is by sourcing verifiable facts from reputable sources, and copyright violations are not allowed. I don't understand to what are you referring with "high quality, accessibly-written off-line content"? Britannica isn't high-quality and journalism isn't written by experts in the field.