People in Photos: "0 Photos Scanned" since Catalina upgrade

I upgraded to Catalina (15.2) over 48 hours ago.

Yet when I open Photos and go to People tab, it is stuck at "0 Photos Scanned".

Photos has been closed for at least 12 hours and it still stays "0 Photos Scanned". My computer is an iMac so obviously it's always connected to power.

I can see that photoanalysisd is never active once I close Photos. Strangely enough I only see it active when Photos is open (though intermittently).

My library has ~60K photos (around 330GB).

I googled for this and few people also have the issue but haven't seen any so