Miners build the blocks, not the pool.
Discussion
That is not true as of today. They’ve stated privately they want to move to StratumV2 where that would be the case, but I don’t see anything on the website publicly committing that that.
There is a mention of it in the FAQ. That it's coming in "phase 2". No dates though.
And you can switch pools (miners) by entering a different URL in your firmware and clicking a button. So again, how does it help decentralize?
You presume you can't switch pools within seconds if one gets too big or censors transactions. You know... How Ocean censors transactions....