BitcoinCash and chain analysis

An interesting aspect with BitcoinCash (Bitmains hardforking altcoin) is that users who want to split their coins and exchange them might be vulnerable to chain analysis companies when not taking a lot of care.

One typical issue is coin-merge:
You use Bitcoins tx outputs as inputs for a larger tx sent to an exchange or coin split service and reveal that you are the owner of all those tx outputs.
If you use a KYCed exchange your full identity is connected to those tx outputs.
But even if you exchange on Bisq where your privacy is much better protected there are some risks due the privacy flaws of Bloomfiters in BitcoinJ’s SPV implementation (see:
Most users are not aware that all BitcoinJ based wallets comes with that privacy flaw. If using company/server based wallets you should not count with much privacy anyway.
For highly technical users those problems can be controlled but not for 99% of the less skilled Bitcoin users. So the chain analysis companies will love that.

It is really questionable for me if we should add BitcoinCash as Altcoin regarding that background.

Another reason to consider it that there will be probably no working replay protection in place, so there might be considerable risks involved.

Beside that Bitcoin Cash is not just another Altcoin but could set a precedent if even slightly successful (what I highly doubt). Do we want that it becomes a fashion to hijack the Bitcoin network and instead of cleanly fork as an Altcoin try to fork off from the existing Bitcoin network? I doubt anyone want to see that.

I tend that exchanges should rather boycott BitcoinCash as an un-ethical, technically risky and privacy damaging adventure.

What do you think?

Ps: Posted here as well:

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I recommend the talk of Amaury Sechet (Lead developer of BitcoinABC):

The more general question is if Blockstream’s Segwit is the path to go or if big blocks are the right path. From my point of view we would have big blocks already since long without Blockstream. Anyways things are like they are today and the real question should be what the incentives behind one or the other chain are - as far as I see it big blocks are straight forward while Segwit+LN firstly does not solve the scaling problem and secondly builds completely unnecessary complexity into Bitcon.

Anyways - as the unlucky event of ETH/ETC split has shown a split will not harm Bitcoin. Basically LTC, DASH and many other coins are hardforks of Bitcoin (even without its transaction history). My recommendation is to take it as it comes and accept the economical reality. I am sure that BitcoinCash with gain at least 20% of the hashrate initially. But if Segwit2x does not play out like expected (eg. 2x does not happen) it has the potential to continue as the dominant coin.