Yes. This decision will most definitely cause a land-grab rush, unless the NCAA overwhelmingly punishes CA, other states will just do the same thing.

It's a pretty big change - my guess is CA's stance will win, because the alternative is massive disruption of the NCAA.

Yes, if auto emissions, minimum wage, contractor laws, and many other progressive policies are any example: blue states often pile on to each others' policies to spread them widely. NCAA shouldn't count on NY, IL, WA, MA, or other big blue states not doing this.

Right, but this CA change is (probably) an unalloyed good for CA, which gives other states even larger incentive to copy it -- whereas the incentives to copy minimum wage or auto emissions or other 'progressive' policies may be non-obvious or nonexistent.