For opensuse tumbleweed users: Installing wireless-regdb like the instructions in the OP seems to be required in tumbleweed as well. After that, I was able to use ‘sudo iw reg set XX’ (XX being my two-letter country code) to set the wireless regulatory domain. Before installing wireless-regdb, iw reg set had no effect.

Note that the above does not set it permanently. In order to do that, I had to run the following command (replace XX with the desired regulatory domain two-letter code):

echo “options cfg80211 ieee80211_regdom=XX”|sudo tee /etc/modprobe.d/cfg80211.conf