The problem is deflation means a shrinking economy.
Capitalism has firmly hitched it's wagon to endless (and therefore infinite) growth. Meaning we are all playing pass-the-(ticking)-parcel and hoping the music won't stop.
All empires fall when they run out of resources. Be it fuel, labour, food (or the land to grow it). Or in the UKs case, intelligence.
The British Empire fell (far quicker than anyone could have expected) because we ran our of money to protect it. Despite spaffing our share of Marshall Aid (that 95% of UK citizens won't know we got) on propping it up.