If you code the rules to be fixed, no updates are allowed, ever?
Good luck with making perfect software, without vulnerabilities or bugs, while the environment in which the software must run is changing all the time.
In PoW, miners volutarily update their machines with new software after improvement proposals.
In DPoS, block producers, representatives or witnesses update their machines with new software after improvement proposals have been approved by supermajority.
Softfork can alone do great things, SegWit is a clear example of that. Hard Fork should be harder to implement, imagine if bitcoin (POW) had 20 retarded witnesses playing god? HF should be extremely hard, not impossible, and should only allow changes in specific sections in the architecture of the blockchain. There are already suggestions on how to improve the governance, the model of 20 witnesses didn't work unless you want centralization, 20 is too low, and the voting mechanism for witnesses is broken. We don't need gods, we need a system that allows a better distribution of power, something better is clearly needed. The current governance system is like the UN, the opinion of 99% of countries don't matter as long as there is a small group of circle jerkers (security council) who decidse who gets what and when. If the distribution of power is not distributed enough then we will always have a centralized chain.