Free instant transfers are the direction of travel, but in the EU, that is a question of regulation, not technology. Maybe in 2030 we will be there :)
But for many transactions, I see that instant would be nicer, but I don't see the crucial need. My employer pays all Eurozone salaries from a bank account in Luxembourg, I imagine it is just a script checking "Initiate transfers on 10 AM, 1 day before last working day of month". Being able to do "Initiate transfers on 23.59 PM of last working day of month" would be slightly nicer, but I don't think it really solves a huge pain point?
Even then, transferring money with SEPA from my Swedish account to friends in Germany, Poland and the Netherlands is pretty much instant, I just don't like the exchange rate of my bank.
I have no idea how you did an instant transfer from Sweden to Poland.
Wise might not had the liquidity in your currency pair, and you had to wait for a transaction to happen in the reverse direction.
(Just speculation)
Its Not true in that Description, also dont forget: SEPA!=Euro!=EU!=EER
Source: Im running a bank. In the EU.
It's a political problem not a technological one.