Czechs aren't "going more and more down", it's nonsense. Though still not particularly good, our situation is certainly better than 5 or 10 years ago. The weakest spot is obviously defense, there's only one player about whom I have little doubt that he's going to become a Top 4 D on his team in the NHL (Hronek), then Hájek, who by all accounts should have a very good shot of becoming a long-term NHL defenseman sooner or later. Then there's a grey zone of players who can make it to the NHL one day but who knows really (the likes of Zbořil, Mašín, Galvas...). Not an amazing pool but much better than in early 2010's when we had close to no one.
On offense, it's much better. Quite a few forwards between 17 - 21 years of age with a very realistic Top 6 potential: Nečas, Zadina, Chytil, Kaut, even the 2020 eligible Myšák and Pytlík, and possibly a few others. We also seem to have a ton of goaltending prospects. Lukáš Dostál, for instance, looks very promising though you never know with goalies.