If you really want to get a handle on the numbers -- and see why this is a great idea -- you need calculate the net present value of the project.  NPV is money in minus money out, discounted to present value.   Money in is the real value of monero at the end of the project, when you plan to sell what you mined.  Money out is initial investment, plus expenses, less salvage value (when you're done mining and sell your equipment) discounted to present value.  Whichever project has the highest NPV wins.  

If you run the numbers this way, the open compute project comes out way ahead.  

There are two ways to compare an open compute project with a GPU project.  The first is to match the initial investment.  This would be a risk tolerant approach, where you leverage any appreciation.  Meaning if monero appreciates, you come out way way ahead, because you get way more hashes for your initial dollar.  The risk averse approach is to match hashrates, spending less upfront on the open compute project.  That way if monero crashes you haven't dug yourself into as deep a hole.  

This approach tends to keep your power expenses in perspective.  It's just one part of the equation.  

OP's points about intangibles are well taken.  I would add that the open compute project is scalable, if you can find a host for the right $ (they are out there).  GPU projects are only so scalable, you run into marginal cost issues as you cross the 15-20a barrier -- where you have to start figuring in the cost of renting and cooling the sort of place that won't ask questions about all those wires everywhere and all those sparks flying -- and the 200a barrier, which God knows what you have to do to make it fly.