Corruption Effects downgrade?

Snapshot: 505fa02aa13a40b0bd4b4aea4c886ce7

For my second gear set “Blood - M+” I’m only getting Leech and Avoidance effects as possible corruption upgrades, and most other effects listed as downgrades - even setting the gear level to 485.
At my current toughness setting (M16) I’m unsurprised to see DPS effects not ranking, but I would have expected the basic stat boost effects to be upgrades even if minor - and definitely not downgrades.

(My other gear sets I’ve reached my expected toughness level and it appears to be ranking effects fine)

Yeah that’s a bit weird… I’ll look into it and try to see why that happened.