You can delete friends but sadly only one at a time.I'm on Vita and PS4: PapaNer
Also, is there any way to batch delete friends? I was playing "Toros friend network" for a while, but have since stopped (because there are no trophies...srsly?), and MOST of them are just spamming "SEND THIS TO 37 PEOPLE AND SONY GIVES YOU MONEY OMGLOLI'MINJUNIORHIGHSCHOOL."
I would much rather fill my friends list up with you forum people :3