They (Arrowhead + Sony) decided to make ps plus sign in mandatory on pc
Just to clarify, PS Plus is not required to play Helldivers 2 on PC. PS Plus is the upgraded, paid version of the PSN subscription. A free PSN account (which is not the same as a PS Plus account) is required.
I know I'm nitpicking, but this is a big issue at the moment for a lot of players, and I want to make sure everybody's making a properly educated decision with their money.