Actual result:
Core trusts index and chainstate blindly

Expected results:
Core loads the pruned index and chainstate
Core catches up
Core compares the utxo - hash with other network nodes
If some other node has different database hash the node will fail to start
EDIT: or ban the liar node

Alternative expected result:
Core loads the pruned index and chainstate
Core catches up
User is notified to add configuration option that the user is aware the chain might be untrusted
The value of the option could be dependent on some kind of hash derived from latest block or machine specific random uuid
This will prevent user to download the configuration file from untrusted source because attacker cannot predict this value