EU hasn't done jack **** to Warsaw for all the things they complained about
You're talking about current times, I'm talking about a general rule since Poland has joined in the EU in 2004. Not always we had a government which was defiant against the EU. And even the current one is only defiant regarding some issues and accepts the rest (since when it comes to the economy they're socialists at heart).
For example: Poland, or any other EU country, cannot have death penalty
because it's against the "EU values". So even if the majority of Polish population would agree to it and majority of MEPs would vote in favor we still cannot do it.
Another thing is that the EU members cannot completely decide about their own taxing system because there's an established mandatory VAT standard rate at 15%
for all the members. This cannot be changed by a country, it comes form the outside.
not following green reforms especially with coal
Yes, I have to give it to PiS government that they've negotiated a special clause for Poland but valid only for 5 years till 2025. It still feels like negotiating with a thief and making an agreement that's going to mug you sometime in the future instead of right now. Hopefully, by the 2025 we'll have a new government with a much prominent presence of Konfederacja in Polish parliament which has much tougher stance towards the EU.
Some EU countries needs to buy an extra emission allowances
from other countries which produce nuclear energy "just because". It's basically a hefty fine imposed on countries with a more obsolete energy sector by those who had time and money to swap it over the decades. I call it a sucker tax
And yes, fortunately, the EU countries still have power of veto which they can used in self-defense. The "EU core" has tried to change that and replace it with a simple majority vote but it failed. Had it passed those would be grim times.
There is nothing nuanced about Polish politics
There is. You just have a different cultural sensitivity.