Isn't being incredibly useful actually a pretty solid way to be valued, especially in the trenches? Maybe 'useful' is just 'valued' in work boots instead of a fancy suit.
And yes, that does seem to happen more if you're wearing work boots, probably because people who never wear work boots assume that, if it can be done in work boots, it can't be as astounding and valuable as it appeared at first, or you would have moved beyond work boots by now.
Usefulness may hold its value in the trenches, but the people ultimately deciding everyone's salary generally aren't in the trenches.
I have been more easily valued for my 'use' by being easier to manipulate. Or, sorry, felt more open/safe. Money spends the same: barely, too much work.
Layoffs? To quote Janet Jackson: 'what have you done for me lately?'