Dollars and orange trees aren't securities, but as soon as I start 'staking' dollars and orange trees into financial instruments which earn rewards, it becomes a security.

Asking 'Is Eth a security?' is asking the wrong question. Asking 'Is <some particular use of Eth> a security?' is the right question. Gensler was in the process of giving such an answer, and was interrupted ~40 times in that four-minute clip. It's really quite embarrassing.