I've tried it and depending on the router, it creates chaos. You don't have fine-grained control over what frequency your device(s) will connect to, sometimes devices roam frequently, and there is latency involved in switching SSIDs so if you're on a zoom/teams call and your device roams, your audio will stutter. And also what tends to happen is most devices hang on to the 2.4 GHz band... since 2.4 Ghz tends to have the strongest RSSI, but also the slowest speeds and most interfence with neighbors given the limited number of channels.
So if your device is connected to the 2.4 GHz SSID, when you go to watch video in 4K on youtube or other services, the video buffers or renders in much lower quality than it otherwise should. And when the SSIDs for each band are the same, you don't know if the device is on the 2.4 GHz band, 5 Ghz band, and now, 6 Ghz band. So you may think there's a problem with your network provider, when the real issue is your device is connected to the router on the 2.4 Ghz band and is suffering from interference from neighbors, especially if you live in a building with 10 or more neighbors.
Having a separate SSID for each frequency allows you to avoid this mess altogether. In fact, the 6 Ghz band was supposed to address the issue of interference from neighbors alltogether since only Wifi 6E and upcoming Wifi 7 devices can use the 6 GHz band (so it was supposed to be a 'clean' spectrum), and also 6 Ghz for 6E can operate on 160 MHz channels without any concerns about DFS/Radar. So it's odd to see this support article from Apple.