It looks like England is about to repeat yet another of the mistakes of the 1992-1999 government in Victoria, Australia. In the late 1960s and early 1970s, Victoria's teachers fought for a registration system, with the unions initially setting up their own. If unqualified people were put in front of classes, teachers walked out.
Then, the 1992 government abolished the unions' registration systems and replaced them with ... nothing.
Thankfully, that government's tenure was short, and after 1999, we had a new government which established the Victorian Institute of Teaching (VIT). This accredits teacher training courses, registers teachers who meet the required qualifications and deregisters those who behave unethically.
There is a lot of opposition to the VIT here. It seems to be from teachers who know nothing of the struggle 40 years ago to win professional registration and who do not understand that professions have regulatory bodies. They complain that the VIT doesn't do anything "for" them. It's not meant to - it's meant to do something "for" the public, just as the Medical Practitioners Board is not meant to do anything "for" doctors, but is meant to do something "for" the public, too.