There may be some truth in that last statement. I was able to find the results from several standard class events in Poland from 2009 to 2013 on soaringspot.com. In general, they have been able to get 40 to 50 entries for a standard class event but a couple of recent ones had entries reduced to half that number. Almost all entries are Jantar Standard 3. In the 2009 nationals there was one LS8 and it didn't win. In 2010 there were two LS8's and two Discus with an LS8 winning. In 2011, there were two LS8's once again and one of them won. In the 2013 Polish Junior Nationals, there was one LS8 and two Discus and they finished in that order followed by 18 Jantars and a couple of other Polish gliders.

So, I guess with only a few of the higher performance standard class sailplanes showing up and these now always winning, they were concerned about two things: the experienced inability to win without one and the effect this may have on entries going forward. They may have judged it better to lose a couple of modern standard class entries to encourage many more in, what else, Jantars.