I feel like the person you are responding to was not meaning software engineering. Electrical engineering, Chemical engineering, Civil engineering, Mechanical engineering, etc are all more likely: especially as what you say about software engineering is definitely well known.
Now, I get we like to refer to ourselves as Software Engineers, but surely you understand he means actual certified engineering firms, not groups of code monkeys, right? Software is virtually never engineering, you'd have to get to a situation like flight control software before you're doing anything legit
If you have never stepped into a domain where you have to formally verify your software, I think you should probably not take too much offense to such a comment. While I admit it may be slightly negatively connoted, I primarily used it to illustrate that the kind of engineering going into making a bridge differs greatly from making your UI widget pixel-perfect or your SQL query from being too polynomial
I believe this is in reference to Professional Engineering firms, which often requires PEs either as owners or in certain roles. As far as I'm aware software engineers are not required to be Professional Engineers in the US for most tasks, nor are SaaS shops required to be licensed as Engineering firms.
NCEES did toy with the idea of a software engineer Professional Engineer license, but it went away due to too little interest. I think it was in part that industry didn't want it because it would give more leverage to SEs. IMO the only way that will become commonplace is if it is forced by regulation.
