I have a similar experience, only visiting reddit for stuff like tech problems and very niche communities. I had never willingly visited the reddit homepage since.
There are a lot of posts now on lemmy compared to before the reddit fiasco but is not like the activity on reddit. The good thing though is that it made me stop my habit of mindlessly scrolling through endless content.
Heliboard was the closest to Gboard imo. It would be better though if it supports Japanese input.