We (in the US) had to add $3.3 Trillion in new debt spending to stave off an economic disaster. That's not what I'd call 'easily managed'.
Too many years of declining GDP, and the government becomes a credit risk, forcing it to pay higher yield on the bonds it issues. Running government services on a balanced budget while GDP is still declining is tough.
Shrinking GDP one year is much different from it becoming the norm.