Aerial mapping replacing ground surveys

I’m seeking opinions and experiences from traditional theodolite & other ground based surveyors who’ve moved on to drone mapping and structure from motion volume calculations. In my experience, I’m getting 2-4% differences between theodolite transect volumes (admittedly a single slice of the landscape) and Pix4D volume calculations from drone aerial mapping (which also gives me ability to get 3d volumes of entire landscape elements). So, my question is: how much variability or “error” is acceptable in traditional theodolite mapping? Do you agree that the future of open area landscape mapping is NOT ground based, but better done from on high (drone or LiDAR), etc.
Please let me know your thoughts.

In my opinion we are already there. The important part is to continue to ground truth the data and understand the limitations. LIDAR and Photogrammetry are very different applications.

Thanks for. Replying jl
Still, I’m searching for what is acceptable “error” or variability in theodolite vs photogrammetry? If I pay for a truckload (assuming it’s weight is the key) of sand or such, and after its dumped and moved around, can I measure the volume precisely enough to match what I know was once in the truck? What % of the true load is acceptable as measured by photogrammetry?

I think 5%