Do you really expect the typical person to set a bunch of passive limit orders on GDAX until they get filled? What kind of user experience is that? I would be willing to wager that 95%+ of Coinbase users are just buying and selling directly on Coinbase (and paying the extremely high fees) and have no idea what GDAX is.
Of course that's the case. I never said everyone does that. I said it's a no-brainer to do it.
Back when investors held paper stock certificates, including bearer securities, which de-centralised ownership recording, shares were frequently lost, stolen, damaged and fought over after someone's death, intestacy, bankruptcy et cetera. Returning to tokenized holding would heap costs currently well managed by the system onto end users. (One would also have the problem of irreversible transactions being incompatible with modern law and securities practices.) "Stocks but on blockchain" is a regression for everyone except the hucksters.
All securities exchanges incur fees, varying based on wherher you’re eating or supplying liquidity. I forget what these are called, but companies like Interactive brokers pass those fees on. Robinhood eats the fees for you.
With coinbase, you pay a 0% fee as long as you use GDAX, which is a no brainer, and place limit orders that are not immediately executable e.g. sell $.01 above the current price or buy $.01 below.
I’m not the parent so I’m not gonna address the tokenization question, but my opinion is that tokenization helps the users (stockholders), but takes power away from centralized exchanges thus the NASDAQ would be kinda crazy to switch to decentralized assets