You should probably bold the second part instead. Not exposing the public key is crucial in this sentence. It simply means, that if you have some presigned timelocked transactions, sending coins from P2PK to P2PK, then obviously the destination P2PK is not yet exposed, if it was never broadcasted anywhere. Which means, that a proof can be constructed, that you know it, and later it can be revealed. Then, even if everyone will know the private key, the previous commitment will enforce the proper destination.

Existing BIPs are not set in stone, they can be updated. I already put my comments in some discussions there. It is more likely, that I will discuss, what is already there, instead of creating yet another BIP. Also because existing ones are not that detailed, so they need to be expanded anyway.

Which is also why we don't need more BIPs, dealing with the same topic. It would only create confusion, and it could end up in the same way, as block size BIPs, where you have many of them, and none is implemented on BTC. Only altcoins like BCH used them to some extent in practice, and for the actually deployed Segwit, block size increase was fully optional, and if it would be deployed without Segwit discount, then we would still have 1 MB blocks.

Thanks for the list.

This is the problem though, as this is going to be the most controversial part of any proposal that involves these methods. If there are good recovery mechanisms for P2PKH outputs then freezing them after some period of time can be more justified and will less likely lead to opposition. However, not having a recovery mechanism for all coins that have their keys exposed and most notably historical coins such as satoshi's alleged stash will cause significant opposition and controversy. Most of the rationale based around that is market-centered, related to the potential of somebody "dumping" these coins and this is not a very convincing line of argument for anyone who is maximalist-oriented (or a maxi). The world will not end in this scenario, there will be turbulence and negative price performance for some time, but we tend to not care too much about that.

I do not see any reason not to implement something like this though in any case. Some could argue if they want to be persistent and annoying about some potential edge-scenarios where this might negatively effect 1 user out of a million but that is not worth considering.

You need to convince them too if you want to have any chance at all of reaching consensus on something like this. If you can't convince them, this is not going anywhere. The best alternative is to fork Bitcoin with such a proposal, but that historically has not worked out well for those that did do it.  

My focus on that statement is solely on historical coins like satoshi's. Scenario (for the question/statement): Assume that users and entities have upgraded (better) or been pushed to upgraded (worse), then there is no rationale for freezing those coins other than market related talk. What other harm could those coins possibly cause to the network or protocol? They literally can't do anything. For all we know it could be satoshi reintroducing his coin, which are assumed to be lost/dead, back into the circulating supply. This has no effect on the network from a technical standpoint.

In regards to the other coins and the situation where users and service providers are getting randomly and suddenly hacked and the ensuing chaos -- there I do agree there are existential level worries. Although even there, as I have noted previously elsewhere, users would be able to submit transactions privately to miners until things resolve. We would take a massive hit (and this kind of chaos is best avoided if possible), sure, but it is not like suddenly you will not be able to transact at all unless you want your coins to be stolen.

You literally quote this in the BIP, and this is a market implication. While you may not be using the exact wording, this is the implication but anyway as I said my statement was focused on those coins.

Which seems like a good thing to you? And for me it is quite a terrible thing. If we can demonstrate that freezing can be done with only hashrate and the major economic players (the fewer the easier), then we will have made a case for government-forced freezing. Forcing users into compliance-consensus to do something like this with a hard fork is near impossible practically speaking, but successfully doing it with a soft fork will create a precedent that we will never be able to fully get away from. We can only hope that collectively we will be able to defend against a future freezing mandate, but shifting from decentralization guarantees of censorship-resistance into hope is not exactly an improvement. Is it?

I'd prefer some dumps in the million range over turning into something like Bittether any day.

In terms of entities or users upgrading fast to new address formats? Sure, I hope so to. In terms of freezing balances? I hope not.