POSTĘPOWY v angličtině:

His thought is progressive.

HIS PROGRESSIVE IDEAS WERE NOT UNDERSTOOD BY SOCIETY

The grammatical form employed here is the present progressive.

Especially over the last 20 years, the purported link between progressive welfare policies and economic failure in the Northern European countries seems to point to the difficulty of sustaining both full social welfare and international competitivity.

The example is a past progressive tense sentence. How was everybody taught when they were learning about progressive tense?

In a progressive tense sentence it becomes the -ing form verb, that is the present participle.

The future progressive tense is used when expressing events and action in progress at some future point, however the example sentence cannot be understood in that way.