I'm not sure they actually are extremely high. It's just that most other salaries have fallen below what we'd normally consider middle class.
Stated another way, the things that software engineers can do with their wealth generally seem like normal middle class things. They can own a home but they can't afford a yacht. They can take nice vacations but they aren't part of the jet set. They can start businesses but generally not in capital intensive areas like resource extraction or heavy industry.
I'd say that software engineers, at least the higher paid ones, are probably on the higher side of middle class; but they are still solidly middle class.
That's the frustration. We and nurses do something that a great many people "could" learn to do but choose not to because the job itself sucks. Not coincidentally, we are also the two specific jobs that were targeted by the H1 visa program signed into law by George H.W. Bush in 1990. As it originally existed, there was a special H-1A visa for nurses and an H-1B nominally targeted at all kinds of white collar worker, but in practice really targets IT.
When some hospital board member says "there's a shortage of nurses", they leave out the other part: "there's a shortage of nurses who will get puked on and verbally abused by patients for $40k/year".
When Mark Zuckerberg says "there are not enough good programmers", what he really means is "there are a not enough good programmers who will work 60 hour weeks for $150k in a Bay Area suburb where a 1,300 sqft suburban condo costs $2M".
I'm glad I got what I could out of this profession and started investing before the post-pandemic job market reduced us from "middle class" to "lower middle class". So far since 2018, I've managed to turn $20k into $1.4M by running my portfolio like Peter Lynch if Peter Lynch had experience in software and biotech.
My only regret is that I paid off my $28k car and $45k of student loan debt early instead of starting to invest in 2015, in which case I might very well be holding $10M and instead lamenting the $1k-2k of money I spent as a child in the 00s on N64/Gamecube/Wii hardware/software that could have Apple stock worth $200k today.
I'm not trying to specifically give you a hard time, but this needs to be called out in the public square until it stops being a hallmark of HN threads: you're passing off speculation and bald opinion as fact.
You don't know how competent the software engineers are in Europe, and saying "$140k for a software job is extremely high" is an arbitrary value judgment.
140k places you in the top 1-2% of the entire planet in earnings.
I can think of 2 US companies I know of off the top of my head that deliberately hire Europeans since they get talent at a steep discount (especially if you pay them remotely). From what I've seen Ukraine and Estonia are considered goldmines of cheap talent. I doubt they are the only ones.
Bald speculation and opinion would be that this massive imbalance between earnings is causally tied to merit to a degree strong enough that we can confidently say European software engineers are as a whole a whopping 50% less competent than US counterparts. This to me is ridiculous, not because it sounds offensive or anything, it's just obviously untrue for Europe. This is just how we've set up our geopolitics with downstream affects being massive imbalance between earnings of countries.
I'm writing this reply not to the lazy commenter, but to anyone reading this thread...
Yet again, we have classic HN speculation masquerading as authority.
Should software developer salaries be comparable to accountants or to surgeons? That's an arbitrary value judgment.
Software engineers have less purchasing power than they would without the H-1B visa program, and that's indisputable. 64% of the visas go to IT workers and 52% go specifically to programmers, which implies beyond all shadow of a doubt that their salaries decrease further than the cost of the goods and services they pay for.
This also impacts non-software tech: see recent layoffs statistics at Intel, what percentage are H1B and why aren't companies required to re-prove H1B necessity?
Can we just over-hire and claim we need H1Bs because we can't find enough talent to fill the rolls, then submit that we over-hired and lay off all the US talent? This seems to be a bit of what happens even if not intentionally.