I had a different experience. I was on 150 mg of Effexor and tapered by 50 mg/month with no problems. Obviously, that’s not everyone’s experience! I was on it for a severe depression—not so much anxiety. What resolved that depression was 2 weeks of SAINT (Stanford Accelerated Intermittent Neuromodular Therapy)—which is a variation of TMS treatment. Even tho’ the depression was completely resolved with SAINT, I was afraid of going off the Effexor—but eventually, after a year or so, I started the above taper. In May, it will be 4 years post SAINT with no recurrence. I understand that in some people there is a recurrence, which just goes to show that there is individual variation in response to treatments.
Perhaps try tapering by 1 mg/month? You can always go back up if you start having anxiety or “zaps.” If that happens, then try a 0.5 mg/month taper. You’ll get there!!