I’m arguing against extremists taking over the country. Any functioning government has to rest somewhere above the political center of gravity. Otherwise, there’s no enough overlap for compromise and you actually do get unrepresentative government.
Representation means they have influence proportional to their number. This is provided by any democracy. The failure point is when a group too extreme to represent the nation as a whole somehow gets power despite this.
America found out what happens when the extremists take over a major party. In fact, we almost lost the DNC to its extremist wing, too.
Luckily, they were too racist to succeed.