It's over a decade since the big SF awards have been any indicator of quality. These days, they're practically an anti-indicator of quality. What's more, they're heavily weighted in favor of a particular type of science fiction book -- and it's talcum-soft. When was the last time Greg Egan was up for a mainstream award?
I presume there’s a voting mechanism? Are you complaining because democracy hasn’t yielded your favourite outcome?
FWIW I might align with you in not finding all that much that I wanted to read in recent winners. That said this years nominations for Hugos have given me
A Drop of Corruption
and
Shroud
I enjoyed the former (and the earlier book in the dance series) and I’m 30% though the latter.