Hi João,
Yes, it’s normal to have this impression, but take into account the specifics of the curves created from the segments.
In the case of Maru’s questions, whether it’s ‘Huanglong Waterfront’ or ‘Armani stairs’, even if he created the project to actually build those objectives, creating a 3D model from a 2K resolution JPG photo taken from the internet (and with a single interax dimension) would only have a certain accuracy anyway, whether you use curves or subdiv.
If there are professionals asking for help in this forum, they should normally take the offered idea, but when applying it to their projects, they should take into account what they learned in college or specialization.
Regarding the architectural projects that are the basis for the construction of a building, I draw accurately, even if on the plan the dimensions will be shown with only one or two decimals. I can always change it to appear to five decimals and the size will remain accurate.
If I import a DWG file created by me (which I know is correctly drawn) or receive a random DWG file, in SketchUp I use it only as a reference, I draw each wall (window/door gap, etc.) by typing the exact dimensions, and I also type the distances between elements, I don’t do them by eyeballing.
eg: A project I worked on and it was built
Thank you for the question!