Therein lies the problem, anyone using the job title 'engineer' by normal conventions, has an accredited qualification and demonstrably relevant experience.
Within the medical device world, the use of the term 'engineer' is commonplace, but not necessarily accurate.

There are many competent and experienced practitioners who have progressed through a more traditional city and guilds route, who could demonstrate the fundamentals in their sleep, but are happy to remain on the tools.
Some people gain advancement through different skill-sets, and progress without that fundamental knowledge up the greasy pole of advancement. Most departments have them, not really an issue, as their forte may be paperwork / communication which is also a valued skill-set.

As regards greater regulation, that particular subject has been done to death.
Be careful what you wish for.