I have a 18’x30’ covered run. My four teenage chickens spend all day in there for now. The poop is not piling up
Some people seem to be born with a "clean gene". It's not just women, some men have it also. Whether it needs cleaning or not, it must be cleaned.
To me, if the poop has built up so that it starts to stink, it must be cleaned. That's generally when the poop gets wet and stays wet for a few days. If it is stinking it is unhealthy and unpleasant.
If the poop builds up to a certain thickness it will be a problem. Under the roosts is a typical area for this. If it gets thick it stays wet and will eventually stink, plus if you or the chicken walks in it you can have a mess. With me that is just unpleasant, but if the chicken is tracking that poop into the nest you need to clean.
I don't know what is happening in your coop, but in a run that size the poop is going to be so spread out it should not be a problem. That's one reason to not go with the absolute minimum amount of space you can get by with, you have to work harder when you go with minimum space.
With that much space I would not clean it unless I saw a problem. I would not expect to see a problem. That's over 4 times as much room as I have per chicken when I'm really crowded and I never clean my run. I don't have to. But if you feel you much clean, that is your business.