This is a very good question! Your question is very reasonable and insightful, and I must tell you that I had thought about this over and over before reading your post. But first, Blackrock will not offer you Bitcoin at a higher price, they will only offer an ETF service.
I get it, but to offer an ETF service they have to hold bitcoin in custody, right? Also, they aren't the only fund applying and there was a new application filed just days ago, so we don't know the total number of ETFs that will function 2 years from now. I don't think there's enough bitcoin at sub $100k for them, not even close.
Now, tell me, why go through Blackrock? All the ETF events are not well viewed, which is why people see it as a big deal. Though a good step that Bitcoin and the Crypto industry in general are advancing.
Because many institutional investors are not like Microstrategy and cannot turn company funds into bitcoin and hold it, but they can hold regulated securities, so the only way for them to get bitcoin exposure is through an ETF. I'd call that a big deal, even if a handful of these companies decide to do it.