> Why do you lack confidence in the SegWit2X developers?
I think the fact that they're pushing a hardfork 3 months after SegWit activates says a lot. We're talking about making all existing clients on a 40 billion dollar network obsolete and open to abuse. Giving only 3 months time to upgrade is absurd. Also, I believe SegWit2X was spawned some time in May? Being generous, that's only been 3 months of development so far.
When it comes to software like Bitcoin, where the slightest bug can result in catastrophe, I want the most conservative developers imaginable.
The development of btc1 (the SegWit2X client), AFAIK, has not been open. Most of it has occurred behind closed doors, with only the merges to the public repo being visible.
Another notable concern is there was a pull request submitted recently against the SegWit2X client (btc1). It changes the "seed nodes" list; adding in nodes that will run SegWit2X software. That's fine, except one of the nodes belongs to a company who's goal is to monitor and de-anonymize the Bitcoin network. For those not familar, seed nodes are the nodes the Bitcoin client initially connects to, from which they can learn about other nodes on the network. Giving a company that is actively trying to make Bitcoin unfungible is ... concerning to say the least.
> It seems the miners would be the last ones wanting a potentially fatal bug. Do they have less to lose if an exploit/honest bug burns the blockchain?
Just because you have a massive mining farm under your belt, doesn't mean you know the first thing about the ins-and-outs of Bitcoin. Mining is such a small part of what is otherwise a massive ocean of domain knowledge needed to understand Bitcoin. The people who contribute to Bitcoin Core have been doing it for 8+ years! And they're a band of cutthroats who aggressively review each other's code. The developers working on SegWit2X have no of those advantages.