Why does the entire blockchain on a full node get wiped out when Core has to get reinstalled?

Makes no sense. The chain was clearly verified and being used by the node. Why does the data get wiped out if Core does? It would make it much faster to sync to Chain Tip if the data wasn't chained at the hip to Core.

What am I missing here? Surely I am not the first person to think about this so I feel like there is something in my logic that is all jacked up.

Chain re-sync now at 13.11% (1 hour and 40 minutes of syncing)