What happens to the price of bitcoin in the short term after the launching of the ETF no one can predict (100k or more, anything can happen). 
HOWEVER WHAT WILL CERTAINLY HAPPEN is the following, because bitcoin financialization means: 
1. Diluted demand for the real bitcoin, the non-custodial, bearer, decentralized, censorship resistant asset. Money will rather flow into the black hole of fiat financial custodians. Anyone FTX & Co.? 2. Discourages self-custody and financial responsibility. You are not your own bank. You are not financially independent. In the long term this means they will be able to control the price like they did with gold. Paper gold claims are estimated at 1000times more than physical ounces. See how this has successfully capped the gold price.
3. Discourages learning about Bitcoin and becoming financially literate.
4. It is very risky. You will buy nothing else than counterparty risk. You will own nothing but a claim on a claim. Blackrock holds its bitcoin in a non-custodial wallet held by Coinbase. Therefore you have 2 counterparty risks and NO bitcoins: shares of the Blackrock ETF and IOU on the Coinbase account.
5. Censorship resistance is gone and the intermediaries can easily enforce third party claims or government/judicial dictats on your "paper" bitcoin claim via the intermediaries.
6. It encourages speculation, manipulation and discourages true adoption (i.e bitcoin real time monetization).
You can advocate for the long term benefit of financialization only if you are (i) stupid or (ii) a speculator who wants to cash in on the price spike and forget about Bitcoin or (iii) if you are extremely naive and do not understand what are the powers and massive forces at play against Bitcoin and their need to control it because they cannot suppress it or own it. Which I explain very clearly in the articles below which one should read before believing in "Santa Blackrock".
PART I 
https://andreleblanc.substack.com/p/will-bitcoin-win-and-foster-a-new
PART II
https://andreleblanc.substack.com/p/will-bitcoin-win-and-foster-a-new-a13