I call this idea the "feed marketplace" as opposed to "feed-as-a-service" which is what @openrank and others are doing. 

The challenge building a "choose your algorithm" is that the most interesting feeds are no longer just "algorithms" or fancy SQL queries.

For most users, what they say they want in a feed and what they actually do is a textbook example of stated vs. revealed preference.

🪐 Building @neynar, join us in /neynar & /nfs | ex-Coinbase | manan19.twitter

yeah had this debate with @manan recently lol

building /neynar & /nfs 🪐 | neynar.com | writing bad casts on /rish 

I love the sentiment. RSS+ etc. 

But modern consumers want relevant algorithmic feeds that aren’t a simple set of heuristics.