Main issue is enforcement. Engineering is a good example. Engineers become licensed have guilds etc. Thing is they tend to work on things that are in the physic

Main issue is enforcement. Engineering is a good example. Engineers become licensed have guilds etc. Thing is they tend to work on things that are in the physical world and if they break they will cause death and destruction. So the government will force a company to have an engineer stamp that this design doesn't suck and hold them liable when it does. More importantly, most infrastructure projects engineers work on tend to have government involvement to begin with meaning that someone with power to enforce the law will decide that it is appropriate to work with a licensed engineering firm. This becomes much more challenging at a typical software shop that is working on some run of the mill web app that won't really impact anyone's life adversely if things go wrong and generally have an opt in mechanism to begin with (i.e. Facebook or Google). I'd say where it would be very very useful is making it so that license software engineers are the one's who sign off on something like Equifax to prevent security breaches, or basically any software that impacts someone's life directly and can't be reasonably avoided (think banking software, medical software etc.)