Zigbee and wifi do clash a bit more, but after I set my channels I’ve never had problems: https://www.metageek.com/training/resources/zigbee-wifi-coexistence/
My zwave has been bulletproof though. I suspect something is wrong with your setup, I assume you’ve tried things like healing the network?
Is your stick on a USB extension cable or hub extended away from your pc? That can help quite a bit.
He was always a scum bag, but 911 made him seem like a golden boy for a little while.