No other engineering discipline has such a low barrier to entry where everyone can self tech themselves at home almost everything people that go through the higher education pipeline can, and then extra on top due to how fast the industry evolves, where even having a degree might not make you qualified for a job today. In no other engineering discipline is all the tooling FOSS.
So the PRO is that anyone can become a SW engineer, but the CON is that when anyone can become a SW engineer you're competing with soo many people on an even playing field that weeding out the wheat from the chaff is tricky and no company had the perfect solution because it doesn't exist.
What other engineering profession things change so fast that tools from ~20 years ago (C, PHP, Perl, etc) are not useful on the job market anymore? What other engineering profession gets hundreds/thousands of applicants per open position? What other engineering profession has such a lack of standardization that every company works completely different, with different tools and different processes to ultimately do the same thing?
In most other traditional engineering disciplines it's not just the university degree or credential that matters to getting in, but a lot of critical knowledge can only be gained from mentoring and learning at the job from graybeards of the industry, knowledge you'll never get if you try to teach yourself, even if technically all the relevant courses and information is freely available online. Not to mention that in a lot of engineering professions the tooling is specialized, non-FOSS and very $$$, so your only chance of touching it is at university or a company who will pay you to get certified in that tooling.