I lived in Sweden for seven years, and this is so far from the truth it's hilarious.
Relative quality of life is garbage in Sweden for a tech worker. Your life will be not that much better than if you work in Carlings selling plaid shirts to hard-rock hipsters.
My Swedish friends have decent jobs and still live unglamorous, frugal lives. As soon as I left Sweden, my quality of life completely transformed for the better.
If you go to live and work in Sweden, where will you actually stay? You can't rent an apartment — the waiting list is around 16 years for a decent apartment in the city. It's even several years wait to rent an apartment in the ghetto.
How did your colleagues find apartments? If they didn't buy places or have apartments provided through their employer, I'm guessing they're sub-letting through Blocket.
For reference, Stockholm's suburbia is places like Hägersten.
If you're a low-skilled worker, QoL is likely going to be better in Sweden. If you're a tech worker, QoL is almost certainly going to be better in Poland.
I might be misinterpreting your point, but it seems like you're taking the position that it doesn't matter that Sweden is outrageously expensive in many regards, because money has no impact on quality of life anyway. If that is indeed the position you're taking, well, it's a trite and nonsensical one.
Your final sentence makes me believe I've misinterpreted you, so apologies in advance if that's the case.
If you're a tech worker in Poland, you will feel far wealthier living in Poland than if you're a tech worker living and working in Sweden. You will be able to live in a nicer home, eat out at restaurants more often, and generally have more money to do stuff with.
Buying things (clothes, gadgets) is a different story, because they can't import the stuff any cheaper than Sweden does, but I don't think the difference there is enough to counteract the general difference in QoL and buying power between living in the two countries.
Edit: Also, to clarify, I did not say that quality of life for a tech worker is garbage. It's actually generally great, as I think everyone here knows. My point is that if you want to reap the financial benefits of being a tech worker, Sweden is not the place to do it.