I am not entirely sure if you juxtapose the legal framework for Danish non-competes and garden leave. But assuming you do: In Denmark you are formally not employed, and you are free (actually obligated) to look for other job opportunities. You just can't, well, compete. So you can not take employment in a competitors company etc.
So, if you're a lawyer, you just can't work as a lawyer. Or at least you need to work for a different type of company which may not be easy to do depending on your specialty. In fact, forcing someone to look for work doing something different seems like an even worse outcome than letting them do whatever personal activities they want for a year at reduced pay.
Except what normally happens for professional jobs in the US is that someone lines up a new job, then they quit (and maybe take a few weeks off between jobs). In general, in the US, not being able to start a new job for 6 months would be a non-starter in many situations. And, while some occupations may be very hot, depending upon your age/experience/etc. being able to just quit and count on quickly lining something up when you start looking seems risky.
I am not advocating this system at all, merely pointing out that in Denmark there are protections for employees and a requirement for the employer to pay.
