It is true that any DSLR can get u great pics for reefing and frags yet a better camera will.always get you better and faster focus, better colors and image quality. I've used the following so far over the last 15 years.
Nikon D70- D200-D300- D750- Z7ii and with each upgrade my pics got better out of the camera which is something to appreciate if u will be fragging and selling corals which means a growing loads of pictures to be taken and processed maybe weekly....
Glass also plays a good part I had good results over the years from a tamron 17-50 2.8 yet the macro 105 from nikon was simply way better for macros, still quality price wise that 17-50 2.8 was great looking at quality/price . Extension tubes were great for macros but focusing was a pain and had to have corals close to the cameras due to the limited working range, might be a plus in a shallow frag tank or then maybe the 60mm macro might be best as it focuses even closer but my tank is 85 cm wide so the 105 was a better choice .....
Phones will get you great pics but compare the pics from a phone vs a camera viewed at 100 percent on a monitor and you'll see how better cameras are.
Raw is indeed great with tank lighting and wb corrections.