Hmm, it seems that my [not baseless] assumption that all these films had undergone 2K restoration at the time they were originally released in the "Slovak Cinema of the X0's" collections, and hence the Blu-rays would use the same masters, was wrong - this one has clearly received a new master / resto! :-O
     And somebody even found out how [not] to use the automatic scratch removal tool or whatchamacallit ;-) that introduced the funky artefacts on the old master: