When there was a Bitcoin hard fork in 2017 and BCH was created, I remember that many casinos, exchanges and other companies were suggesting people to withdraw bitcoins during the fork because they weren't supporting the fork.
That works, as long as users are dealing with Bitcoin. Now imagine an ETF holding a million Bitcoins in the future: "withdrawing" all Bitcoins means selling them. The Bitcoin market will crash hard, and boom again when they buy back after the Fork.
Then, after some months or probably after a year, everyone did it differently, they donated people with Bitcoin Cash that was equal to their balance.
I think it isn't and shouldn't be their responsibility to take care of every fork and they won't do that because then they will have to approve the ETF of that fork, just my two cents.
I guess we're going to disagree on this. A Fork is like dividend: any other ETF takes care of the dividend for it's users, and in exchange they charge their users a "fund fee".
Here, different (stock) brokers advertise with "dividend leakage": depending on how they deal with taxes, you may or may not be able to get back the paid dividend tax. That's a difference of about 0.1-0.2% per year, and it makes a huge difference in the long run.
It's probably a matter of time for Bitcoin ETF brokers to offer something similar: if one Bitcoin ETF keeps any "Fork dividend" for themselves, and a competing ETF gives it to customers, the latter will be more attractive to the informed investor.