Mine is washed river sand (granite I believe from our local river) I had a yard delivered by dump truck from our nearest bulk place that carries top soil, compost and such.
I don't see any problem with using it as a base and organic stuff on top.
As you can see people have different opinions and experiences. I have droppings boards also. I used to put a layer of sand on them. But it is easier to use a flat shovel and scoop all the poop away than the kitty litter sifter many are fond of.
No I can't and won't clean daily. I used to and it took forever. The poo/sand doesn't stink when dry. It's when it rain that it does.
Like so many things, what works great for some might not for others. I have found in locations that get tons of rain, they *usually* have ground that drains nicely and accommodates the weather, with exception to a few puddles here and there. Getting to know our land at our new location was one of the things I did when we first moved here from the desert.
To me sand... is just a big kitty litter box with poo juice left behind regardless of how much droppings you remove. Once I experienced that I switched it up and now have the organic stuff on top. No more sand on my poo boards, I just shovel it out weekly maybe sooner or maybe later depending on load and weather. I did a lot of research, and chose sand... I like using around here and there and having it available for grit... but CANNOT recommend it as an only base..
Yes the sand may eventually make it to the garden. But with enough (82+ birds), you have to start hauling that crap off your land! Some seasons I go through 250# of feed per month, that's a LOT of poo.

Which means throwing away the sand. There comes a point when chicken poo is just garbage and not garden gold.
Now you have both sides of the story and can make a better informed choice for YOU.
Regarding the washed river sand... it is a lot like little pebbles with some fines. My birds do not dirt bathe in it. They like dirt to dirt bathe in.
Yes, my family would be fine to not chat about my chicken management issues either, especially poo. Good luck.