It’s in maintenance mode. They may still support it for legacy Chrome apps (Chrome OS) and manifest-2 browser extensions. For the “drive by” open web, they had an origin trial for a while that you could register for and which would throw your PNaCl apps a “lifeline”.
But for all intents and purposes, WebAssembly is now on par (and beyond) what Portable Native Client supported. Some things were easier in PNaCl - threading support comes to mind.
