Would central banks decide not to react to an inflationary shock?

All central banks have now switched to a strategy of maintaining an expansionary monetary policy until full employment is restored (which can take different forms: "average inflation targeting", "yield curve control" , and "spread control" in the euro zone). But what would happen if inflation were to return and become markedly - and not only slightly - higher than the inflation target? In reality, central banks would have a strong incentive not to react to a rise in inflation. Such a lack of reaction would: Lead to even more negative real interest rates, and therefore facilitate rapid deleveraging; Boost share prices, which could be affected by the fall in earnings if the inflation is a result of a faster rise in wages; Obviously prevent a rise in interest payments on debt and therefore a deterioration in borrowers' financial situations.