As far as California goes specifically, the most recent attempt AB 9 is apparently going to make it a massive pain in the ass for players to get registered.
Instead of just being able to sign up from their computer, they actually have to go to a business front to register their account.
I believe the intent is to help provide protection against opponents who have issues over underage gambling, etc., but it would be a major obstacle to getting games going.
Unfortunately I think the "in person" clauses might be more complicated.
Adelson says he's against online gambling because he's concerned about protecting people.
We know the real reason is money.

Here some tribes and card clubs might be saying this "in person" clause is about protecting people.
It could be more about money. Specifically, encouraging online customers to become
active brick and mortar customers by getting them familiar with the brick and mortar locations.

Borgata said the online demographic is separate from the brick and mortar demographic.
The good news is this lessens canibalization concerns.
The bad news is it could be part of the logic behind these silly clauses.

NJ doesn't have these silly in person clauses and their players are still well protected without them.

In my opinion, the best thing that's happened for regulated US online poker so far is Delaware and Nevada making an agreement that allows them to share player pools.
Agreed. Liquidity is key in poker.
Smaller states are dead if they don't pool players.
Even California won't reach its potential if it doesn't pool outside the state.