The Arrowverse ended when The Flash concluded last year, though shows like Legends of Tomorrow and Batwoman were cancelled without ever receiving proper endings.
On the plus side, Arrow had a fitting series finale (as did Supergirl) while Superman & Lois' characters were moved to another universe.
It all started with Green Arrow, though, and in an interview with Showrunner Whisperer, executive producer Marc Guggenheim revealed exactly how important the Emerald Archer's TV series was to The CW.
"Shortly after the pilot got ordered to series, Peter Roth [president of Warner Bros. TV] took us out to lunch and basically laid out for us, in incredible detail, the reality that if Arrow wasn’t a hit, there would be no more CW," he explained. "So it was the pressure of having a show and keeping the show on the air – that’s one thing – but now we also have the pressure of keeping the whole network on the air. That’s another thing."
The CW relied heavily on its DC TV offerings for a long time. However, as ratings declined - as did profits - the network pivoted and, under new leadership, has moved away from scripted dramas. The Arrowverse's early importance to The CW can't be understated, though.
In the same conversation, Guggenheim reflected on including Smallville in Crisis on Infinite Earths and why we didn't revisit Clark Kent (Tom Welling) and Lois Lane (Erica Durance) in the final chapter. Unsurprisingly, it came down to money.
"Why didn’t we have Smallville? I’ll be honest with you. I think it was two reasons - Number 1: it never occurred to me until I got the question on Twitter that people think we did blow up the Smallville universe. So part of it was that, and part of it was, we had obviously seen Clark and Lois in episode 2 [of Crisis on Infinite Earths.] For the most part, the ‘going around the horn’ [closing sequence montage at the end of episode 5] was to see all the universes and all the characters that we didn’t get to see."
"If I could have done it all over again, it would be awesome to just have a shot of Lois and Clark on the farm, kissing, for the go-around-the-horn-sequence. But yeah, sorry, I dropped the ball on that! We only had Tom for a few hours, but also, here's the thing: under SAG rules, an actor don't get paid by the amount of time they spend on set. They get paid by the number of episodes they are in. So if Tom was contracted for episode 2, and if Tom appeared in episode 5, that would trigger a completely different payment. We certainly didn’t have the money for that, but that really wasn’t a factor. It, quite frankly, just didn’t occur to me."
A tight budget was always an issue for the Arrowverse and it's a shame that closed the door on Welling playing a bigger role as Superman in Crisis. However, just the fact he and Durance showed up meant a lot to Smallville fans (funnily enough, Lex Luthor actor Michael Rosenbaum has previously confirmed he declined to appear because he was offered such a small amount of money).
You can check out the full interview with Guggenheim in the player below.