BTC Liquid Network is not decentralized and does not purport to be. It's a federated sidechain, that is... it's a blockchain that runs alongside the Bitcoin blockchain (using a two-way peg that lock real BTC on the Bitcoin blockchain and issues an equivalent amount of Liquid BTC on the Liquid sidechain) but blocks can only be added to the Liquid Network sidechain by some of the handpicked members of the federation.

You are conflating the original BTC network and a lot of the other projects in the cryptocurrency / token / stable currency space.

Every time there was a new token that was 80% reminded or was governed by a central company, the original cryptocurrency enthusiasts cried fowl.

Most people don't read the fine print, don't read the founding white papers, and don't care about the differences between the protocols and the networks when they should.