And then Czechia in 2021 randomly decided it's not worth it? (Russia did not cut access to their resources as a result anyway). Does not make sense.
The breakthrough in the investigation came only post 2018 as a result of Skripal poisonings where the same agents were involved. It took a while to connect the dots.
The EU, Germany in particular, was not interested in making a big deal out of it for fear of getting cut off from the Russian teat. German economy was set up to run on Russian gas and oil and Germany has a lot of influence over Czechia so there was likely some pressure to keep things quiet. But in 2021 there was enough evidence on who did it and what was being planned to take action.
Because Germany is the biggest ally of Russia in the EU and has investments in Eastern Europe that benefit from cheap labour available in the region and cheap oil and gas from Russia (well, no more), so it was not interested in upsetting the status quo.
Vanishingly small amount of facts that affect us are proven in court or by scientific experiment.
When living on this world, one must do a lot of “speculation”, to derive most probable explanations based
on limited information available. I guess one could call it “personal opinion”, “informed opinion”, or even “expert oponion” depending on the context.
In this specific case, worth remembering, that speed of investigations depend on resources allocated to it; resource allocation is easily impacted by politics.
Here is an unrelated example, but it illustrates an attempt to appease Russia: https://www.bbc.com/news/world-europe-14202371 (there was European Arrest Warrant for ex-kgb guy over old eastern Europe stuff; in 2011 Austria detained him, but then swiftly released him within 24 hours)
