The thing is that the people who actually need to use it for pacing (basically TTers and people entering long hill climb events) will also be the ones who don’t need to rely on the ramp test as they will have race and training results to go by. I don’t imagine anybody is sitting on the start line for a 40k TT A race with only a ramp test result to guide their pacing. Apart from anything else, even if the ramp test was a highly accurate estimation of 1 hour sustainable power, it would be an estimation that was specific to the indoor setup. Could easily be a few % off by the time you factor in all the potential differences from riding outdoors.
Personally I do quite a bit of TTing and long hill climbs and find that power targets need to be taken with quite a big pinch of salt anyway. If it’s an A race for which I’ve tapered then I’m often capable of putting out better numbers than anything I’ve done in the lead up (which is the point of tapering!). Figuring out the number on any given day is more of an art than a science and factors in RPE, HR plus all my experience of tapering, testing, racing, etc.