You are right of course. The orientation on EU and withdrawal from Russian trade agreement was a big mistake at the time. They should have known they won’t sell aircraft engines or nuclear reactors or even Chevrolet cars in Germany. And since they have no market they have no revenue to keep their base up to date or at least to pay their workers.
Ukraine’s more fundamental problem was and is that corruption and the absence of rule of law scare away investment and lending. As a rule of thumb, former communist countries are hard put to create and run a capitalist society. A shambolic kleptocracy is the more common outcome.