> Are "power users" disappearing, or are they just being ignored?
I believe they are mostly ignored.
A power user is a user, who doesn't fear the technical outcall. (S)he wants to get work done and uses a computer as a serious, professional tool. Sooner or later this will require this kind of user to step into configuration, the command line, etc. These users will accumulate IT knowledge auto-didactically, by visiting forums, mailing-lists, etc.
However, they come from many different positions and professions. And as such, they are a moving target of many, often highly specialized, communities. Not the typical customer base a large corporation wants. The large corporation will delegate such communities to "consultants", which those communities either can, or can not afford. I am not an archaeologist, but I could imagine, that archaeologists may benefit from tablets, that can do photos on-site and a document format, that let's them keep track of their excavations, link those to relevant data, etc. Photos like this [1] clearly show a pattern, that relies on coordinates. However, I guess, they are notoriously underfunded and nobody cares anyway.
> Software (and online services) has been in a race to the bottom for over a decade.
I wholeheartedly agree.
I remember the times of ActiveScripting on Windows. It was a great (and much needed) idea, that, however, has been positioned at system admins only (the most typical power user in a Windows environment, typically just some secretary or coworker, who is ready to do it, than a full position) and thus never really took off. Same for XML. Just because software-engineers don't like the format, it must not mean, that there is not some people being "document-engineers". Not everybody, who wants to use a computer programmatically, works at a Web/Cloud startup, etc.
[1]: https://www.researchgate.net/profile/Virginia-Butler/publica...