There are plenty of hacking devices on the market equal or worse than this. The truth is you want these devices available in the public so people are award of them and nerds can learn how to protect against them.
The malicious inclined wont care about legal availability and some tinkers will make them if not only for the technical challenge.
Besides the reason given by @[email protected] which is a very real situation rarely considered by policy makers.
Sometimes laws don’t always align with morality. What morality eventually means is always subjective but many of us carry a deep desire for objective justice and are strongly opposed to going against their own moral code.
I generally don’t break laws because the ones i encounter tend to make sense, most traffic laws. But a law also does nothing to stop me if i see no sense in following it.