That's expected. Any movement that starts small and gains momentum will inevitably be diluted.
This is why it is important to ensure that the core principles/values are correct early on and there is a mechanism in place to propogate them or otherwise prevent against corruption. Before things start blowing up.
Bitcoin is exciting because it is very good at enforcing the core principles via code and consensus, regardless of what newcomers may want, even a majority of them.
And it got a lot of things right from the start: immutability (mostly), limited supply (eventually deflationary), basically decentralized, trustless, secure, programmable.
I do worry though that some of necessary "core" bits were not really in at the beginning and are difficult to add later. These include: privacy/fungibility, scalability, tx speed, full mining decentralization.
Fortunately, the core devs seem to agree and are working on all these aspects, as are other projects such as zcash.
As Bitcoin becomes more popular or mainstream some people will withdraw their support for X or Y reason, that's why there is an altcoin community, and yes, some of those projects are crap, but they are small enough to have the liberty and freedom to add more features. The nature of Bitcoin prevents the centralization of its development.