The end result is exactly the same.
The difference is that you can install an iso on a computer without an internet connection. The normal iso contains copies of most or all relevant packages. Although maybe not all of the latest and most up to date ones, the bulk are enough to get you started. The net install, like the name suggests, requires an internet connection to download packages for anything except the most minimal, bare-bones configuration. The connection would hopefully be nearly as fast if not faster than the iso and be guaranteed to have the latest updates available which the iso may not. While such a fast connection is usually taken for granted nowadays, it is not always available in some situations and locations, it is not always convenient, and some hardware may have difficulty with the network stack that may be difficult to resolve before a full system is installed or may require specialized tools to configure or diagnose that are only available as packages.
In almost all cases, the netinst works great and is a more efficient and sensible way to install. However, if it doesn’t work well in your particular situation, the iso will be more reliable, with some downsides and redundancy that wastes disk space and time.
Things like windows updates and some large and complex software programs and systems often come with similar “web” and “offline” installers that make the same distinctions for the same reasons. The tradeoff is the same, as both options have valid use cases.
While it sounds a bit hacky, I think this is an underrated solution. It’s actually quite a clever way to bypass the whole problem. Physics is your enemy here, not economics.
This is kind of like trying to find an electric motor with the highest efficiency and torque at 1 RPM. While it’s not theoretically impossible, it’s not just a matter of price or design, it’s a matter of asking the equipment to do something it’s simply not good at, while you want to do it really well. It can’t, certainly not affordably or without significant compromises in other areas. In the case of a motor, you’d be better off letting the motor spin at its much higher optimal RPM and gear it down, even though there will be a little loss in the geartrain it’s still a much better solution overall and that’s why essentially every low speed motor is designed this way.
In the case of an ammeter, it seems totally reasonable to bring it up to a more ideal operating range by adding a constant artificial load. In fact the high precision/low range multimeters and oscilloscopes are usually internally doing almost exactly the same thing with their probes, just in a somewhat more complex way behind the scenes.