Algorithm feels a bit weak, not catapulting things up the comment section hard with enough force.

Either way. This is a good thread with lots of thoughts that are still worthwhile. One thought I'm having about some of the drop-off is that we need a method re-engage people that drop-off. Having something like a weekly or bi-weekly email that goes out with a list of the top 10 or 20 threads would remind people that we exist for those who might accidentally fall into user-churn due to daily routine changes that can affect user habits.

User churn is going to happen one way or another, activity is a permanent downward slope in every community, we need to grow faster than user churn while also finding ways to re-engage the users that do churn. Lots of people don't intentionally stop viewing a site, they just drift away for one reason or another because something else takes their interest or something in their life (work or school changes) causes a routine upheaval. Everyone only has x hours per day to dedicate to various different things and because we're humans we're creatures of habit so we build routines around the things we do. But when people's routines go through an upheaval like that it opens a bit gap where anything else can accidentally replace things that were formerly part of routine.

On that note too we should be routine-building. Though I think the megathread does that and generally speaking coming back to view the new hottest threads once per day is also a natural routine-building format that reddit's format is built around. Although ChapoChat seems to present a much too quickly moving bunch of threads, I still strongly believe we should have at least 4 of the top of the day threads on people's front page at all times.

I think what someone else suggested here about default light theme has merit. It's preference to people, those that like dark themes will switch to dark mode.