I studied at a technical university at its faculty of electrical engineering, but those who study at a "normal" university indeed go through the usual three years and are not engineers.
I guess the main difference is that I learned about analog circuits, semiconductors and all that, while those other guys didn't.
I don't have any special professional certificates, though I could optionally enroll on a course allowing me to work with voltages up to 1000V.
The title "ingénieur" is not regulated, it is a job title and anyone can have it if the position calls for it.
What is regulated however is the engineering degree ("diplôme d'ingénieur"), only some schools recognized by the state ("grandes écoles") can deliver it. It gives you the right to call yourself "ingénieur diplômé". Internationally, it counts as a masters degree.
As far as I know, it is a french system with no equivalent in other countries, and I don't know of any foreign school, even among the most prestigious that can deliver a "diplôme d'ingénieur".
Administratively, regulated professions (including doctors, lawyers, architects, etc... but not engineers in general) are regulated by the ministry of work, while the engineering degree is regulated by the ministry of education.
I am well aware of all that because my school (EPITA) went through the process of getting approval from the "Commission des Titres d'Ingénieur" while I was studying there so it was a pretty hot topic. The result is that I don't have a "diplôme d'ingénieur" (but I have a "degree in engineering", equivalent to a regular masters degree, love the play on words) but the next promotions do. My job title is still "engineer" in any case.
I've held an "engineer" title at my day job from time to time, though I'm not an engineer and have no engineering degree. Only a couple of engineers at my work site have licenses. On the other hand, my brother in law was a nuclear engineer, and all of the engineers at the power plant were licensed.
One thing you'll notice is that small companies that do contract or consulting work will call themselves "research" or "technology" rather than using the E word on their web page.
We need to stop redefining terms.
I've never heard "instinctively doing things without conscious choice" to be engineering. That opens it up so wide it's meaningless - is blinking to rewet my eyeballs engineering? How about farting to relieve internal pressure?
And "empirical" explicitly means you consciously understand the reasons, so your comment is self-contradictory as well. Basically, words have meanings and you don't seem to know them.
I could be stretching, but to me, this is very conscious and intentional work, perfected through experience and there are many way to get it wrong. What exactly would we call this?