I watched that entire video twice.

Speak Freedom you god-darned commie!

Probably because the show is about a former hero who gets back in the game. In the Arrowverse Oliver Queen was/is the first modern hero(The JSA were around in WW2 obviously) so having someone floating around prior to that might mess with their timeline.
Also the world they're building for this show might have had…

Saturday Night Live? More like Saturday Night Dead.

Didn't he play Black Lightning back in the 90s?

Have you ever had pizza that was so bad you wish you could go back in time and fix it?
It was perfectly justified.

And Rose McIver joins in via satellite to challenge Adelaide Kane to a rematch whilst wearing their Power Ranger character outfits.

I just checked IMDB, you are correct, as almost everyone from Canada was in it.

Probably because she's busy dealing with the Daxamite invasion. Don't you know that Alien Invasions, Star City being threatened by terrorists/mutant armies and Speedster villain attacks all happen simultaneously across the multiverse?

Almost a guarantee. They might let it float on its own for a little bit however. I was kind of hoping it would be set in Supergirl's universe, that could do with a few more characters floating around and let her have a crossover that doesn't involve jumping across universes.

Naaaah, Barry will get a bad pizza and go back in time to order a better one and that will reset the timeline to zero so that Arrow can have another five years of Island Flashbacks!

Lighter Lightning!

They'd better have a seat over there.
This just became a three-way crossover event!

So basically they're like every female character on the show aside from Thea and Moira.

Jury's still out.

Why did I watch this show before I watched "Better Call Saul"?

I know its been a while but you were kind of close. Ward dying whilst floating in space talking about Daisy.

I'm not old, I'm vintage.
It's bodacious.

They've been trying to sacrifice a virgin but unfortunately too many people on The AVClub are using Adblockers to see the recruitment ads.

That was half a fuck-you(a fu-ou if you will) and more so that they'd have an even number of episodes left for the last night of regular airing(13 episode season meant there was always going to be an odd episode left to air somewhere in between).