`RewindBlockIndex` was made to allow nodes upgrading to new consensus rules post-segwit fork to 
download new consensus data (i.e witnesses) without having to go through a whole IBD. It has been pointed than now really few pre-segwit nodes care to upgrade and that this logic may be irrelevant.

See https://github.com/bitcoin/bitcoin/pull/17737#discussion_r358514335 in review  of #17737 for more context pointers.
{
    
    
    
    if (!LockDataDirectory(false)) {
        
        return false;
    }
    return true;
}
bool AppInitInterfaces(NodeContext& node)
{
    node.chain = interfaces::MakeChain(node);
    
    
    
    
    g_wallet_init_interface.Construct(node);
    return true;
}
bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)