Bitcoin will become more decentralized when we have more competition in node software. Core being primarily community driven development is great, Knot's being an alternative that changes a few things in Core is great too. This is not enough though, we need MORE alternatives if we are to truly be a robust network. Imagine there were 1000 competing clients for node software. Or 10,000. The more independent of each other node clients are, the more stable the network will become. If a client changes something that's not popular, the change will die. But if the change ends up being popular, the other competing clients will implement it too.