A) Assuming PoW is the best way to secure a blockchain, it still has huge overhead and low performance. All that's required is an alternative method with lower overhead, even if it's less secure, to survive into the future and not die to eventually kill Bitcoin since it will provide lower transaction fees, and most likely higher performance as well
"All that is required?" You act like this is no big deal. It is a big deal, and it is quite likely it doesn't exist. "Even if it is less secure" does not work, by the way. You would have to qualify that with it only being slightly less secure. and then further qualify in what ways it is less secure ("secure" is not really a one-dimensional scale)
F) PoW mining facilities are such large, physical attack vectors, that coins utilizing PoW would either become completely subjugated by first world government powers, or just plain outlawed out of existence for a variety of reasons from fabricated terror links, money laundering, or being an ecological disaster.
PoW mining facilities don't have to be large. Outlawing big mining facilities would likely be the best thing that could happen, because that would shatter them into a million smaller pieces that could not be effectively regulated. Subtle pressure is perhaps more problematic. See below. Governments are not (always) dumb though; maybe this is why no one is really pushing banning.
H) Has "first mover advantage". Some people think this is an iron clad guarantee of success and everything else will be defeated, but I think this only applies if the protocol can actually fulfill it's intended roles in the first place. Whether it can or not is unknown.
First mover advantage is overrated anyway. Historically only a few first movers actually ended up dominating. How do you make a law out of something that requires cherry picked exceptions to support? Seems like bullshit to me.
Maybe first world mining would continue, just not in datacenters, and would be the equivalent of getting caught with a marijuana farm by the police after they notice your electric bill.
If that's true then we are home free when it comes to mining because countless people grow weed and these busts are routine enough to be part of the landscape, with no real effect on the ultimate market situation. PoW with 1/10 the number of mining facilities as there are grows would be very secure, very decentralized, and highly resistant to being undermined by regulation (unlike Bitcoin now run by a few big farms and pools). But see above of course. If governments don't ban and start busting people then this doesn't happen.
I tried to put out an unbiased view at all the options. For a long time I heard people like Warren Buffet say things like "Bitcoin is rat poison", "The blockchain has value, but the coins don't". You want to attribute this speech to just saying, "Well, he just doesn't understand how it works", but to some extent this is true.
No, it really is "he doesn't understand how it works", or he does (or more likely people who work for him do) but he actively wants to undermine it. "The blockchain" is nonsense without a native currency. Even PoS requires the ability to issue native tokens in order to incentivize people to do it (and even then in current PoS systems, many don't even bother). Hash chains (which is what you are left with if you remove the native issuance) are nothing new and not particularly interesting.
The bigger question behind all this in my mind is whether crypto actually solves any useful problem that anyone cares about. Outside of gold bugs and some anti-Fed zealots no one really cares about "fixed supply" and all that stuff. The existing banking system works pretty well for swipe-your-card-and-pump-gas. Likewise for e-commerce. With Paypal, Swipe, etc. even ordinary people can do convenient payments via the existing banking systems. Where is the compelling use case for crypto coins? I'm not sure it exists (outside of a complete collapse 10x worse than 2007 that makes people demand something radically different).
Overall a good balanced post and a refreshing change from the usual pure-hype/FUD dichotomy with little actual thought.
