You keep repeating this to anyone who'll listen but it won't make it true.
Like you, and around the same time, I returned my noisy 7700K iMac to get a quieter one. Although it wasn't the CPU I changed, it was the 3TB fusion drive. I got one with an SSD and have never had any problem with fan noise since. The other thing you never seem to mention is room temperatures. Perhaps these tests that influenced your thinking were in warmer environments ? Typically mine is in the low 20s C. We had a long hot summer though and I still didn't hear my fans.
Nearly a year and a half since release, these iMacs are still the fastest single thread macs in the lineup (despite what you said about the new mini). All things considered, I think they are probably the best bang for buck macs at the moment, unless you have a heavily threaded workload, in which case the pro options are better.