Bitcoin (et al) is/are not fully decentralized in the sense that a core development team actively maintains and proposes changes, even minimal ones. While it's true that major updates require broad consensus and may be rejected by nodes if controversial, we should acknowledge that certain points of centralization exist, particularly around development and decision making. These often overlooked aspects now carry more financial consequences, especially as Bitcoin becomes more intertwined with regulated financial instruments and political power.

For example, now, many L2s around Bitcoin are fully depending , and influencing on a future change: enabling again the OP_CAT opcode [1].

[1] https://github.com/sCrypt-Inc/awesome-op-cat