One alternative is to ban politicians from using these private websites as "official pulpits". As private websites they are under no legal obligation to allow

One alternative is to ban politicians from using these private websites as "official pulpits". As private websites they are under no legal obligation to allow anyone to use them. If politicians want to communicate with constituents, then let them do so through government websites. Why does the US government not create its own "Twitter" service? Government websites are subject to laws and regulations that private websites are not. Unlike private websites they would be required to honour free speech protections under existing US law. As we know, the private websites have incentives to allow politicians to use them as pulpits because it drives "engagement" and, in some cases, because they want to sell political ads or ad services.