Let’s not risk another community split by bailing out unlucky investors. Proponents of a fork should start a Parity Reimbursment Fund (PRF) instead.
Let's be clear here. No one likes to lose money. Hence arguments can and will be found to support either side.
I hereby propose an outside-the-box solution that is NOT a fork.
Parity should stop focusing on the low-hanging fruit. they shoul not use their high-level contacts to persuade VB et al. to make a reimbursement through a hard fork of Ethereum. Parity should stop making compromising EIPs endangering the future market position of Ethereum.
Instead they should take full responsibility and start a reimbursement fund for their unlucky customers. The whole Ethereum community can then donate money to that fund. The costs for at least a partial reimbursement of said customers/investors will be neglectable in comparison to a hard fork that will easily split a $50B project just another time. And for most unnecessarily.
If Vitalik et al. are persuaded to take this EIP seriously and start pushing it into the actual Ethereum code base. It'll be obvious that there exists a single point of failure in the system. And we'll see that failure get exploited extensively!
tl:dr; Parity fork supporters put your money where your mouth is and make unlucky investors whole again instead of endangering the long term success of the whole network.