I guess don't really see how "utils" encourages this mistake nor am I sure it is that common. I mean, the idea that most, if not all goods are not linear is 101-level stuff.

I don't understand this comment. I'm assuming the linearity of a good refers to whether its utility is a linear function of how many of it you have? In that sense, this is unrelated; this is a much broader issue, having nothing to do with how the utility of something varies with having multiple of it.

Although I suppose it is related in that, if "linear good" means u(kx)=ku(x) (where here u(x) means the utility of having x of the good), then no good can be linear in that strong sense, because the equation isn't even meaningful! Edit: But, as I should have realized earlier, this is really a silly equation to consider in the first place, as it's the difference u(x)-u(0) you really care about, not u(x) itself...

It is a bad idea to artificially increase the apparent distance between the work done here on decision theory and the work done elsewhere. There is way too much of that already. It makes for bad press and is phyg-like.

I don't think this does increase the distance in any substantial way.

It's not a breaking change (like, say, putting functions on the right, or declaring electrons to be positive). It's not very-similar-but-slightly-different in a way that would cause confusion (like using tau instead of 2*pi, or using Delta(z) instead of Gamma(z+1)). It's not replacing any key term that someone would be searching for (like using "meager" instead of "first category", or "false hit" instead of "type I error", or "computably enumerable" instead of "recursively enumerable"). It is a direct translation, of a term that people won't be searching for and isn't even strictly necessary, in a way that's quickly transparent and nearly self-explanatory. I am honestly having trouble imagining a less obtrusive change. So I don't think this is putting any substantial distance there, let alone approaching phyg status.