I think this comment wasn’t supposed to be an argument for the existence of Israel, but rather directed at the initial premise. They are challenging the assumption that support for the Israeli state and support for the conflict in Gaza are one in the same.
Also she wasn’t even really interrupting him. If you watch the clip, she was muted and he was easily heard over her. It wasn’t as if she was really steamrolling.
You can tell it got under his skin in 2020, and this was just a pathetic way to “get back” at her for being a woman who asserted herself in a debate.