Typical arduino users do not use JTAG. Instead, they use serial to send messages to debug. This is how embedded developers debugged their code for long years. Especially that the micro is so small and you projects will typically be simpler. For example, if you are reading dirt moisture in your plant and then displaying that on the character display, do you really need debugging? Your code is about 10 lines of code
We see arduino and NETMF very different but they complement each other very nicely.