There may be case when people who bought Bitcoin ETF later learn about self-custodial and no longer wants to use 3rd party. With withdraw option, that means they could avoid hassle of selling Bitcoin ETF, buy Bitcoin on exchange and withdraw it which could cost more money and time.
Oh yeah certainly. I meant that if they want to buy Bitcoin in self-custody in the first place, then perhaps buying straight through an exchange is faster and cheaper. If they decide to withdraw at a later stage then you 're correct.
Food for thought again, but imagine a day where ETFs allow the withdrawal of the underlying asset (BTC in our case) and many people have learnt about self-custody and try to withdraw from the ETFs, essentially diminishing the AUM (assets under management) to minimal amounts. Would they allow a massive withdrawal? We come to the same argument again. It's not our Bitcoin, unless we have its custody entirely on our own.