The real problem isn't XT. The real problem is that there is no good means to break a serious impasse.
XT is a tiny problem - many alternatives exist to get bitcoin to scale. But XT taught us one thing, Bitcoin is extremely fragile when the core devs can't naturally reach agreement in conversation.
It's not Bitcoin that's fragile per se, just the current prevailing, yet warped, concept of open-source that makes it appear so. The fact that Bitcoin is both open-source and a consensus mechanism means that anyone can not only read the code, but also alter it and make their own clients with their own custom rules to govern the network. However, these rules only come into being if enough users securing the network agree with them. This is more powerful than most people realise.
Anyone perceiving an alternate client with a fork proposal as a threat, or worse still, calling it an attempt at a coup or dictatorship, or thinking that all the core devs have to agree all the time has fundamentally misunderstood the concept of open-source decentralisation. Just because the majority of the users securing the network agree that Bitcoin Core is the correct rule set to govern the network at the moment, it does not mean that this will always be so. Being a developer for Bitcoin Core does not grant you any special power or authority over the network, nor should it.
The definition of "consensus" in Bitcoin is not a single group of developers agreeing on a rule and the network enforcing it without question. The true meaning of consensus is that
any developer can
propose a rule and the network
chooses whether to enforce it or not. Ergo, Bitcoin is inherently resistant to authoritarianism. It would be incredibly difficult for a single developer to seize control or enforce rules that the majority disagree with. It's actually quite beautiful and I can't wait for the rest of the world to catch on. If politics and governance works in a similar fashion at some point in the future, we might have something that actually resembles the democracy we are supposedly meant to live in.