Relevance of expertise

There is a common argument that because the Bitcoin Core developers have the most extensive technical expertise in Bitcoin, we should give their opinion on any Bitcoin-related topic more weight than we give to anyone else's opinion.

To draw this conclusion in general would be incorrect. Whether this is justified depends on whether the disagreement in question hinges on the subject that the Core developers have the most expertise in.

Imagine Core developers are the world’s best experts on topic X, but just one of many groups with valuable insights on topics Y and Z. Imagine that a group of industry wallet developers agree completely with Core developers on topic X, but disagree with them on topics Y and Z. Imagine that this group of industry developers have equal expertise in topics Y and Z as the Core developers. In this case, favoring the position of Core developers in this disagreement because of their expertise on X would be unjustified.