i recommend using the official "opt out" line. it should be set, if not, you did not officially "opt out". and if you want, you can choose to hide your ssid as well. i think it is a bit of overkill and anyone with wireshark, for example can find your "hidden" ssid.
if you have an open source hardware firewall running pfsense or opnsense (with vpn installed on firewall) connected to an open source router (travel routers are great since the signal usually doesn't reach the road) with openwrt or dd-wrt you should be well protected, just remember spoof your mac address before connecting it to your isp's modem the first time.
even better if you choose to not use wifi, but this is threat model dependent.