He said he’s not interested in building a new Apollo-like app in an interview with The Verge.

It’s hard for me to build another thing. If it just evaporated again, it would be like a double breakup. This has been so exhausting for the last few months. The amount of work it would take to port all the API endpoints over to Lemmy or Kbin or something, that would be a gargantuan amount of work that I’m not sure I have the capacity for. Source