Making a statement, even a controversial one, is not an invitation to debate.

Think about it as a real-life situation; If someone is out in public and just makes a controversial statement out loud, are they now obligated to sit by and engage every person who disagrees with them in a full-fledged debate? What about if 50 people simultaneously call out this person and demand a response? 100? 10,000?

This is also assuming every opponent is acting in good-faith. Is the person allowed to discriminate the bad-faith questioners? or do they have a duty to justify themselves to any and all questions?

The point is that Twitter and other social media are just that - social media. Not debate media. Much like at, say, a bar, people are allowed to make jokes and share opinions with each other without having to derail and argue with any schlub who disagrees with them passing by the table. Part of social interaction is making statements and sharing opinions, without necessarily wanting to fight over them with strangers who happen to hear them. Dissenters are free to make their own statements disagreeing with the person, and you can have discussions over it if you want to, but by no means is the first statement maker obligated to engage with any/everyone who wants to disagree.

Sealioning is the word for this phenomenon. Randos on the internet think they are entitled to a person's time and energy when they are clearly not interested, which is just not true.