Same bssid(mac address) for 2.4ghz and 5 ghz

one of my friends said that, if i want to use band steering properly on openwrt, i have to use the ssid name same, also the bssid (mac) same for both 2.4ghz and 5ghz on a single router.
my question is,is that right? or i should use same ssid name and different bssid(mac) for.2.4 ghz and 5ghz?

(OpenWRT:) If you want real band steering, you need to install „usteer“ or “dawn“ and configure properly.

Maybe get familiar with both, test them, make some experience and then report back with questions or issues.

Same ESSID, encryption settings and PSK, yes.
Same MAC, under no circumstances at all.