Would have been a lot more feasible 20 years ago if they nipped it in the bud by charging 4chan, but they didn't and it's honestly too late now. Especially after Prisma Illya, Kiss x Sis, Oreimo, and Eromanga Sensei have been out for about a decade. It would be a logistical nightmare and most likely would be an expensive endeavor as every single defendant would have the CBLDF behind them.
As for Jersh back in the Blockland days, there really was no need to encrypt his stuff back then. My point still stands, Jersh was into something MUCH worse.