I mean exactly what I wrote.

Russia currently holds about 20% of what was Ukraine. Whatever is left is currently 80%, but it has been degraded by nearly 2 years of war, both demographically and in infrastructure.

The war is not over. What percentage and in what state it will be in at war's end is almost completely unknown. The only sure thing is that the longer the war goes on, the worse state "whatever is left" will be in when the war is over.