Same and double checked and noticed I wasn't logged in so i logged in and I see still 30.

I also only see 15, logged in or not. And it is also showing some posts besides Ask/Tell.

I never use this section, though.

I see 30 and a more button, even on a different browser incognito

I see 15 and no "more", even logged in.

Is it based on browser? I'm running Google Chrome.

I checked in Firefox and Duckduckgo

I guess it could make a difference whether you swear or ask nicely :)