They do not have to, but they risk being slashed if they add transactions that are not “correct” as per the network.
The link I provided shows this coercion via OFAC compliance.
The link I provided shows this coercion via OFAC compliance.
Technically you can still obtain 32 ETH on the market, permissionlessly set up your own beacon-, validator- and execution clients and wait until it's your go to send out txes.