“One sort of optional thing you might do is realize that there are six seasons instead of four. The poetry of four seasons is all wrong for this part of the planet, and this may explain why we are depressed so much of the time. I mean, spring doesn’t feel like spring a lot of the time, and November is all wrong for autumn, and so on. Here is the truth about the seasons: Spring is May and June. What could be springier than May and June? Summer is July and August. Really hot, right? Autumn is September and October. See the pumpkins? Smell those burning leaves? Next comes the season called Locking. November and December aren’t winter. They’re Locking. Next comes winter, January and February. Boy! Are they ever cold! What comes next? Not spring. ‘Unlocking’ comes next. What else could cruel March and only slightly less cruel April be? March and April are not spring. They’re Unlocking.”
The non descriptive names are better because they can be consistent across different countries not depending climate
July in Croatian - Srpanj
August in Czech/Polish - Srpen/Sierpen
because for obvious reasons harvest time in Croatia is one month earlier than in Czechia
though your example for April in Polish makes no sense
April in Polish - Kwiecien
May in Czech - Kveten
I'm pretty sure flowers are blooming (it's not about flowers, but about blooming) in Czechia earlier than in Poland, so the names should be reversed
though even English/German/Slovak months are not without their issues, October should be eight, November ninth, December tenth based on their Latin names, this video makes fun about it, but honestly I seriously like the proposed system:
The French Republican calendar used a few years after the revolution was also in this spirit. However these names do not export well across the world, notably a problem when as a colonial power like France you export your language and customs.
—Kurt Vonnegut