Is decentralization the real reason the New Republic failed?

There are alot of arguments against it, like the galactic republic existed for 25k years even though it had its problems with corruption and a very bloated bureaucracy.

I feel like the new republic is very decentralized and planets and systems are mostly self governing, also i bet all that trust and goodwill for the republic is gone and people are far less trusting of a strong government.

Only thing the empire did good was how centralized it was despite everything relying on Palpatine. Empire was pretty peaceful if brutal for 19 years.

The ideal scenario is a galactic republic with elected governers in all the planets and systems, not local rulers.