im on the 10:1 train but with a catch
we arent factoring feed in/out, which shrimp are quite good at
one neon tetra's metabolic output from cellular respiration sure beats a shrimp, but shrimp put far more little mice poop looking pellets into a tank imo so in the end, if you aren't cleaning a tank very well i think both species are pretty polluting given their differences in cellular waste output. we still input quite a bit of feed into shrimp tanks, thats their bioload too.
thats just my guess.