Poland would still be a dirt poor ex-communist country
First off, communism was overthrown a decade and a half BEFORE EU and PRL system was crumbling well before then, and yes, there was plenty of catching up to do in the early 90's, but by late 90's and early 2000's Poland was already in a great place - hence why it was taken into the EU and given more INVESTMENT funds than any other nation that joined in 2004 or at any other time.
And no, in the 90's there were plenty of Mercedes, BMW's, and even a few Maseratis in Wroclaw not to mention Warsaw. My uncle had one of only 3 corvette's in the country and that was in some poor ass little town of 100k people. Plenty of people travelling to and from PL/US/Germany etc. If you can a bag you could do it whether it was PRL, 90's, or today. Although wages were smaller, costs of living were far smaller relative to income than they are today. There's no buying a hectare in the city outskirts or suburbs for $10 $20k today that's for sure.
If we didn't have punks like Kwasniewski and co bringing in brigades of foreigners to buy up assets for way below market prices (which were already far lower than anything in western Europe or even Czechoslovakia)
What the non-Poles fail to realize is that most Poles, namely the conservative types, who allowed PiS to sweep the election and are the reason for PiS having 2-3x the support of 2nd place losers PO, aren't willing to give up their sovereignty and take in a bunch of radical migrants 'carrying all sorts of diseases and protozoa (as our president famously said) nor will they oblige the EU diktates just because it means an extra 11.7 bln a year for the state to spend. Besides, the gravy train is over. We're expected to be a net payee. Better to just leave now than have Polish citizens' money being spent on Ahmed and his soccer team of kids or Swedish cross dressing kindergartens.
And if the frogs in the EU leadership don't keep a muzzle on their migrant loving german counterparts, it's not going to end pretty - and not for PL but for the EU. Each battle EU has picked with Poland they lost - there was never a 2 bil fine for migrants, no 100k a day for bialowierza, their article 7 is totally doomed, and now even timmermans along with 4 other EU nation leaders that Poland does NOT have to listen to any BS about constitutional courts to keep receiving money