Thefuck? The EU has been making everything conditional on privatization, deregulation and generally adopting more capitalist models in practically every aspect of government. You're calling this left wing??
A few examples of the demands: sell off our largest and state-owned bank; decouple, deregulate and privatize electricity generation and sale; open the up publicly-owned railways to private operators; increase the minimum age of retirement...
But I'm referring to the withdrawal of cohesion funds from countries like Poland and Hungary under newly invented rules like needing to share "EU values". These values aren't defined or written down anywhere, but the only countries that seem to violate them are those with conservative parties in power. The moment the conservatives are no longer in power, suddenly the country is in compliance with "EU values" again.
Plenty of conservative governments are in the EU. Freedom and democracy - which mean an independent judiciary and free and independent press - are not left-wing ideas!
So yes they are written down. And rightly so. Being conservative is fine but telling others how to live their life is not.
However this is indeed not the reason for the withdrawal of funds as others have mentioned.
Given the limits of oceans and seas, and Russia and Turkey to the east, there's not much more of Europe left that hasn't joined. They've actually succeeded in uniting almost all of Europe - pretty effing incredible, an historic achievement that will be admired for millennia.
The big wave of accessions from former eastern bloc countries was partly driven by the promise of huge transfer subsidies, but those are now being made retroactively conditional on things like only voting in left wing parties and who knows what else in future. Not so directly appealing anymore.