It’s pretty short, there’s not much else to it. Czech President Petr Pavel is a very realistically-minded military man and a very strong supporter of Ukraine, so he’s probably just voicing what he sees as likely.

The Crimea thing is the sort of thing Zelensky is talking about when he says the West doesn’t want too much victory. It’s not that enough leverage to grab Crimea is impossible, but it would be politically catastrophic in Russia, which might mean civil war in a nuclear power bordering Europe, and so the West doesn’t really want it to be possible.

Crimea, I think, is still a possibility (and one which the US has voiced support of), but if Crimea is retaken, it will definitely need to be an entire undertaking after Russia’s presence in the rest of Ukraine is entirely broken, not simply as fait accompli when the Russians are kicked out.