And now we need to talk about Future! Dark! Felicity (The “Calculator”)’s lair.
We need to talk about how literally everything about it proves that in the flash forward future,
First off, can we all agree that if Felicity were really to go dark, she would never-in-a-million-years style herself “The Calculator?” Like, never. She has enough daddy issues. If she ever became a villain, she would NOT take a parallel path to his. I mean, even excusing everything else, she’s just more creative than that (and I think she has expressed some serious disdain for the name in the past).
Therefore, the only conclusion we can draw is that she chose that name because of its association. The Calculator (Noah Kuttler/her father) is certainly googleable, dark-internet-searchable, mythic in certain circles, and - most importantly - personally connected. So it’s a clue. It’s not seriously Felicity’s villain name.
Secondly, the tennis ball arrow passcode thingy. I DON’T NEED TO SAY ANYTHING, OBVIOUSLY.
Therefore, the only conclusion we can draw is that Oliver - who he is and who he was - is/was still very important to Felicity. She still loves him. Which means that if he is alive and able to be with her, he’s with her. (And he’s definitely alive. And if he can’t be with her physically for whatever reason, THERE IS NO WAY IN HELL THAT THEY’RE AT LEAST NOT IN CONTACT.)
Also therefore, the tennis ball arrow passcode thingy existing in that lair proves that Oliver - what he stands for - is centrally important to whatever her mission she is on in that secret lair. In other words - her mission IS NOT EVIL.
THIRDLY AND MOST IMPORTANTLY. The fern.
Two things: The fern exists, and the fern is dead.
We know that the fern itself is symbolic of several things:
Oliver himself: the fact that he is dark but he “thrives on low light” - his light being Felicity
Felicity herself: she is the spot of brightness that can thrive in dark conditions
Overall, then, it represents Oliver and Felicity’s relationship - the symbiotic nature of their love for each other
JUST THE FACT that the fern is there, then, SHOWS US IN VERY OBVIOUS TERMS that (up until it died, which couldn’t have been that long ago and might have only happened since Felicity was “murdered”) what Oliver stands for is still very important to Felicity, that she was still lightness in dark conditions, and that she still loves Oliver.
AND THE FACT THAT IT IS DEAD is clearly an obvious attempt to suggest that everything it stands for has likewise died. That she has lost her light, that she has lost her love, that she has actually died.