So much fear and panic for no reason. None of those scenarios you've described are particularly likely. There's only a slim chance that any exchange who knows what they're doing would willingly stay on the chain with less support. They would risk damaging their reputation if they lost their customers money as a result of following the wrong chain, so there's no incentive for them to do that. The only exception to that would be MPEX, as they've stated they won't accept any changes, but screw MP and all of his crackpot supporters.
The network hash rate has stabilised, but hasn't dropped by any significant amount. The network is in no way, shape or form "weak". In fact, it's more than twice as strong than it was this time last year. The fork will only go ahead with majority support, so what you're saying about the fork being easy even if no one supports it is simply nonsense.
If you think a fork "destroys centralisation", you clearly have no idea what the word means. The users securing the network decide what software they want to run. If the majority decides to support a change, that change goes ahead. Anyone, core dev or not, can release modified code, but it's down to the users whether or not they decide to support that modification. There's no logic in saying "one group of developers thinks A, so we all have to agree with that, but if you agree with this group of developers who thinks B, suddenly it's centralisation". You can't have it both ways. If you genuinely wanted a coin where a majority of users can't change the protocol, then you would actually want a centralised, closed-source coin where users don't have a say. If that's what you want, I'm afraid you're in the wrong place.
I honestly can't tell whether you're just giving into hysteria through lack of understanding, or if this is a deliberate attempt to FUD. Either way, most of what you've said needs some serious rethinking. For someone considering themselves a "true Bitcoiner", it doesn't seem like you've grasped certain core concepts very well.
He's just spreading nonsense and one should ignore him. As already previously mentioned Bitcoin had a much higher block size limit. The change right now is not optional but is rather going to be a necessity.
There are people around here that think that their ideology is the right one, but in most cases it is false. Forking isn't a "nuclear option", it is a way to introduce changes/features that can't be done with a soft work.
Changes to the block structure, difficulty and other fundamental rules require a hardfork. Generally hardforks are used to correct something while softforks are used to introduce something new/useful (e.g. P2SH was introduced via a soft fork).
There is no way hardware can keep up with that doubling.... this is not a wise plan..
Why do you think hardware can not keep up with it? What in the last 25 years shows anything towards that idea? I think we will most likely be fine.
It should be able to keep up if companies stop releasing products that are only minor upgrades or rebrands. The internet speed/bandwidth might be a problem in places such as China. However, hopefully something else is going to be released that will be able to manage the amount of transactions that we need.