Let's be real, most improvements in terms of financial management or in other words, money, was in terms of making it EASIER for most, if not all people. We all started with bartering stuff, trading item x for item y in the past, but not all items could be valued properly, so coins were made. From there, countless changes were made to arrive at what we call fiat right now. The decentralized system is actually the same as what we have now, BUT, it makes us move more specifically. Unlike in fiat/centralized systems, the difference is for centralized, it's like asking for someone to walk to a place for you, while decentralized is asking for YOU yourself to walk to said place.
I like Bitcoin and all, yes, but let's be real. The entire world liking Bitcoin, sure possible, but using it? I doubt it. There are a lot of benefits that people see in fiat or in the future CBDC, and I doubt Bitcoin being decentralized is enough of a factor to actually influence that, most especially since a lot of people don't really know the value of decentralization, or even if they did, they don't really care since they want easier lives.
You make some good points but even if people cannot see the value of decentralization right now that does not mean they are not going to see it in the future, how could this happen? With a global currency crisis of course.
Since bitcoin exists some countries have already experimented problems with their fiat currencies and for the most part we see the people use the dollar as a refuge against the high inflation they experiment but we have also seen some people using bitcoin to achieve the same effect, once a currency crisis happens that is global in scale people will have to look for alternatives and gold will be one of those but bitcoin will be one of them as well and that is when people will understand the value of decentralization for a currency.