On the yellow&gold = power&love theory: Spamton chose love when he signed Tenna’s contract, Tenna chose power when he went for the phone instead of Spamton.
Tenna coveted Spamton’s power because it was something he lacked; he had no power to make his own choices or to go to different darkworlds like Spamton did with the benefactor’s help, due to his nature as a TV Tenna is entirely reliant on lightners and has no agency. He will always be TV, while Spamton abandoned his old purpose and made himself a new one. Unlike most physical object darkners Tenna can never really go anywhere; as he says he’s a “giant electric box plugged into the wall.” Tenna is resentful and scared of how helpless this makes him, and craves power as a result.
Spamton coveted Tenna’s love because it was something he lacked; lightners never looked at him and he was always destined for the trash as a spam email. Tenna had a whole family of lightners he mattered to, and Spamton had never mattered to anyone before. Tenna naturally drew the attention of lightners, a desire all darkners share, but something Spamton could never dream of having without help. His benefactor gave him freedom, the power to “make his own choices,” but they couldn’t give Spamton attention, and despite himself Spamton still craved it.
Spamton’s choice to share his secret with Tenna because he loved him went against his prior contract with the benefactor. After signing Tenna’s contract, Spamton immediately lost all his power; both his wealth in his sales and his agency after his transformation. Over time Tenna gradually lost all his love when the lightners stopped watching him; but in that moment he immediately lost Spamton, who Tenna failed to prioritize his love for.
Neither of them ever experienced “real” power or love in the first place. Their mutual jealousy towards what they thought the other had and they themselves lacked was a product of their own insecurities and outside interference. In the end Spamton was always a puppet and Tenna was never a part of the family.
The tragedy of their relationship is that what primarily broke them apart was outside forces acting against them. Tenna loved Spamton, he wanted to be big together, but in that one moment with the final phone call his desire for power superceded his love. Spamton wanted power, he was resistant to signing Tenna’s contract, but he chose to weather unforeseen consequences out of love for Tenna.
And now that they both reached too far and lost it (Spamton’s power, Tenna’s love), their desires have pendulum swung in the other direction: Spamton desperately claws for any inch of power to become Neo and attain true freedom, attempting to rebuke any love he once felt. Tenna clings onto any scraps of relevance to the lightners that he long lost as a lifeline, and is still haunted by guilt years after Spamton left.