While reading (another question about hibernation races) I recall this story, and while it might be the one the other OP is asking, but I think its different.
EDIT:I read this within the last year or two. Not sure of its age.
I recall a story (Maybe a short story) where a multiple species (200-1000?) in the galaxy would be awake for a few years/a Decade? Then hibernating for 1000-10000 years. (Sometimes longer if they have been doing a few short hibernations in a row. Then they might be out for 100,000 years) Observing all the other "Fast Life species" that never advance well (gaining intelligence?), unless they learned to hibernate. I think they gained new pathways in there brains to gain intelligence while hibernating, and their bodies expelled toxins that built up while awake.
One of the hibernating species discover a new species that is prospering without hibernating, and start monitoring it during frequently awake cycles. But they become concerned when the new species is NOT fitting the pattern and their prosperity is accelerating rapidly.
Unfortunately, the monitoring species end up needing a Long Hibernation cycle before they can adequately convince the congress of hibernating species that there is a danger so the congress can decide whether or not to wipe out the new species.
The conclusion is told years later, but early in the long hibernation, when the monitoring species is woken early, and discover the new species has spread through out the galaxy (Apparently the new species was us.) But Humans, despite discovering the monitoring species were trying advocate wiping out Humans before they hibernated, has developed a treatment that eliminates the toxins so they never need to hibernate again.
It is possible that this was a story on the HFY sub-reddit.