You don't want "unlimited" SSIDs-- you want a RADIUS-assigned VLAN and a single SSID. The credentials used to associate determine which VLAN the traffic dumps into. Your UniFi gear will do it.
Of course, a lot of consumer-grade hardware won't do 802.1x so you end up stuck with needing a bunch of SSIDs (and wasting air-time on beacons).
Or just one SSID, where you directly put all the Androids, iPhones, IoTs, and similar garbage in addition to your trusted devices connected via a overlay wireguard network on top in full mesh configuration.
You will not have to trust the potentially outdated wifi firmware, that is quite likely vulnerable to all the latest holes in wifi security.
Of course, a lot of consumer-grade hardware won't do 802.1x so you end up stuck with needing a bunch of SSIDs (and wasting air-time on beacons).