> If you can get your employer to give you fixed salary in a deflation, your spending power goes up.
Yeah, but you can't. BTC is deflationary because of built-in supply constraints. Its trivially obvious that you can't expect a fixed salary in it unless you have a shrinking pool of employed people.
> If the employer adjusts down, your net buying power doesn't decrease if prices adjust to increased value of money.
If the employer adjust down at or slower than the pace of deflation, your buying power doesn't decrease, just as it doesn't with an inflationary currency if your employer adjusts up at or above the pace of inflation.
Of course, if your employer is paying you in Bitcoins, they need to get them from somewhere, and with a deflationary currency which encourages hoarding and discourages both spending and investment, good luck with your employer having much success with that.
> Those who by and large run the world right now sit on their laurels letting their money (albeit, in "risky" investments rather than a box growing in value) make them even richer.
Investments aren't money, they are things purchased with money.
> While their money might be productive, they more or less aren't contributing anything else, and they do it in self-interest.
Right, currencies managed to be mildly inflationary harness the self-interest of the rich to produce diffuse benefits (which, unfortunately, are often counteracted by things outside the currency system itself, but that's a different issue), while currencies designed to be deflationary harness the self-interest of the rich to produce diffuse harms (which, unfortunately, are often aggravated by the same things outside of the currency system that mitigate the benefits of inflationary currencies.)