it depends the reason why people go for AIO coolers would mainly be for overclocking, but it's not just that, heatsink cooler like Noctua are amazing sometimes better performance than AIO's.
Heatsink is quieter whilst AIO can be heard apparently, another reason would be for Aesthetics, omg AIO looks so cool haha so yea one of those, yea the 9800x3d has low TDP, but that isn't really what you go for it's when a game company has optimised that CPU to run well on the game, sometimes i've seen that CPU hit 80/90c just because either game not optimised or driver issue, but there is a youtube video regarding that chip online running too hot and hitting 80/90c when gaming, but i think it might of been patched? please do your own research regarding this chip.

I also hope this helps you:
https://www.corsair.com/uk/en/explorer/diy-builder/cpu-coolers/air-cooler-vs-aio-cooler-which-should-you-buy/?srsltid=AfmBOoo2zmwMaNhnnNq24uQsvBwc5lpQmYDhHgQycgFrdGc7_g2Eepus