Modern mainstream feminists are not anti-porn by default even though they are often critical about it. How do you think men would react if feminists were anti-pornography like they were in the 60s and 70s during the 2nd wave?
Would the backlash be so powerful to warrant an annihilation of the movement? If I remember correctly, the feminist friendly government of Iceland banned pornography but I hope they don't have problems to bypass the ban.