I can imagine that I might refuse to use a system based on the metric measurements, so I voted no. But it would have to be pretty obtrusive, and there would have to be very comparable games equally available.
Basically I think the metric system is a stupid system based on fetishizing ease of conversion between units at the expense of having units that actually organically make sense for things humans do. It came out of an Enlightenment era belief in eliminating doing things based on custom and tradition in favor of doing them based on Reason (which I'll capitalize, in the style of the time), and has never shed the basic arrogance wrapped up in that way of thinking. It is not a system built to human scale and can't describe anything without a cumbersome amount of syllables. It was imposed on the world by a condescending intelligentsia, and it's fundamental hubris is not challenged enough. It an extremely useful system (and sometimes vastly superior) in an abstract academic context, but as applied to the real world, units based around what is customarily convenient based on the natural world, biomechanics, grouping objects for transport, or other concerns of commerce or life in general are often less cumbersome than units which exist only because of a x10 relationship to some other unit. All systems of measurement are mostly stupid and arbitrary, where the metric system gets on my nerves is that because it's arbitrary units are derived from other arbitrary units based on Reason it's proponents think it's intrinisically less stupid when, in many contexts, it is actually slightly stupider. And that sort of arrogance I can't abide.
However if I were to reject an RPG based on usage of the metric system, it would probably not be because of my hostility to the system, but because it either used it extensively in a way that was aesthetically really obtrusive to the setting of the game, or just demanded too much visualization in metric from my not very metric accustomed brain. Still these would just be points against a game for me, not dealbreakers in their own right.