A fast moving field. There are a number of outlets that do fan testing on occasion. I don't know of any reliable source with rigorous testing standards.
You can also spend a lot of money on fans, so when you say the best, how much are you willing to pay per fan?
Also depends on if you are using water cooling radiators, or have a heavily filtered intake what fans may be most suitable.
Airflow, Hybrid, Pressure (Static Pressure Optimized) for radiators.
Most of your RGB fans are built in a hybrid style so they can be used as case fans or radiator fans and I would call most of them equal outside of bearing life and RGB features, interconnects, etc.
If I were buying a pile of mid-range case fans today, probably Arctic P12 Max for my radiator heavy setup. (Though direct replacements for my 140mm Phanteks are still out there, in the form of the Phanteks PH-F120MP V2)
Cheap airflow fans, probably Thermalright TL-S12.
But that just covers 120mm.
Other popular choices are be quiet! Silent Wings 3, and Pure Wings 3. Then we start breaking into Noctua pricing territory with the A12X25, or the Thermaltake 30mm thick fans.
I'm still partial to Corsair SP120 for swapping fans on cheap air coolers. I often pick up Gammax 400 or other cheap CPU coolers when they are on sale and swap in those for quieter operation.