After Smallville ended, the mythology continued in the Smallville Season Eleven comic book, but getting to see Welling’s Clark Kent back on the small screen is a big deal for a lot of folks, and will likely draw even more eyes on “Crisis on Infinite Earths.”
As Marc Guggenheim noted, without Smallville, Arrow and the birth of the Arrow-verse probably wouldn’t have happened, so it’s fitting that the show will be represented through Tom Welling at the very least.
Smallville ran from 2001 to 2010, a time when superhero stories slowly became more popular on the big screen, but barely had a presence on the TV front, which certainly isn’t the case nowadays.