Every one of us? My impression was that hysteria over the dark age was confined to a vocal minority. I suppose we can pull up the old threads to check.
You misunderstand. I'm not saying everyone assumed and was angry that there was a galactic dark age. I'm saying no one did or could have gleaned from the pre-EC ending what the ending was "supposed" to be, as delivered in the EC. I'm calling BioWare liars. The EC is not what the ending was intended to be. It was changed in response to the complaints, clearly. It wasn't an issue of clarity or too much room for speculation, it was an issue of quality.
Before we continue, we should probably be clearer about what we mean by a "dark age." Without the relays trade would be strangled for..... well, we don't know how long. We don't have a time-scale for the relays being repaired either pre- or post-EC. Could be centuries either way; nobody we see getting home in the EC slides has less than centuries left to live, which is long enough to get back even if the relays were never repaired. Some colonies, particularly the human ones, don't seem likely to have enough population to maintain their technology in this situation -- without economies of scale there are too many pieces you need to keep making -- and would likely revert to much lower technological levels; 19th century, maybe? (FWIW, I was in favor of a sequel where the relays had never been repaired, and large areas of the MW had reverted to barbarism.)
From a purely logical, lore-based position there is no way they could have gotten the relays functioning again in any sort of timely manner. All of the advanced technology was based on Reaper tech, which is no longer active or usable, so how do relay repairs even begin? If you ignore the fact that the actual logistics/engineering of the relays is still largely unknown at that point you're still left with non-functioning ships, non-functioning equipment, and a crippled galaxy that was already on it's last leg. If the relays were so easy to figure out then the Council and Cerberus would have been making their own relays already.