HAOS has more support for running additional add-ons/applications next to HA itself, on the same machine. In my case, that would be a Lenovo M710q Tiny loaded with an i7-7700T and 8GB RAM. Plenty of resources to spare for things like my Zigbee coordinator, NoLongerEvil (Nest thermostat), go2rtc (webcam shenanigans), Mosquitto broker (MQTT), Node-Red, Music Assistant, Aircast (for apple stuff), and other things.
TL;DR - It's mostly personal preference. If you already have a bunch of containers running for home stuff, then by all means, run HA in Docker. But if you prefer the "all in one box" approach, go for HAOS. I don't mind the "all in one box" approach, as long as it's related to the core function of HA.