I go totally cold turkey every year for ~2 months and have for years (more than a decade). It's a fascinating experience each time, as close to a reset as I think you can get without hard drugs. I sleep better but feel more weary and tired without coffee. I no longer get serious withdrawal when I stop drinking it.

The happy medium for me, and YMMV, but I find now that half-caf is quite satisfying and less sleep-disruptive.