Clark Kent became Superman at the end of Smallville, but the execution was controversial with the CGI, close-ups with CGI cape, and shirt rip. If we get those things with Tom in Crisis, then as Primal Slayer pointed out it's more about him not wanting to be Superman. It has nothing to do with earning it.
That doesn't make sense. If his character is shown in a suit—in any form—then it establishes him as Superman. If anything, not wearing the suit on his body, but having his character appear as if he is, suggests Welling is fine with people associating him with Superman. There were times in the past when Welling was even willing to play the character on the big screen, so I doubt that remained a concern for him. He may just not want to wear the suit...
now. Why? Because, unlike Routh, he didn't have months to get into shape to wear it, and there wasn't a long time for anyone to make him a decent one. He is also likely only going to be in the crossover briefly; reportedly he returned home to LA after his day at the farm set. He has an infant son and just got done a pretty long TV series shoot abroad. He's not as close to the production as Durance, who played Alura and lives in Vancouver, or Tyler and Routh who are established CW DCTV characters.
Back when
Smallville was originally airing, though, they had different problems. The head of the network, Dawn Ostroff, wasn't supportive of the show. The budget was incredibly strained the final season, and for the finale, both because of paying Rosenbaum to appear, and because the network wasn't very generous. They had to reduce their shooting period for new episodes down to just 7 days just to stretch the money. In addition, the finale took place during a different time for WB/DC. Unlike now, when they're more flexible with the various versions of the characters, they were strict about duplicates.
Early in the final season they had implied that Clark's suit was going to be Routh's (i.e. Donner/SR Superman), which
Smallville aligned with most, but by the end of the year
Man of Steel and the New 52 were about to occur with both characters likely wearing different suits. Instead of showing Welling's Clark in a clear version of his own suit or a previous version, and to honor the show's mission as a prequel, they hinted at the suit so as to allow one to project onto the end of
Smallville's origin story any version's future. That worked well for Welling who genuinely felt that to the show's premise was rooted in Clark's journey and earning the suit more than him being Superman and wearing it.
As for as the trending comment, it's Brandon Routh's KC Superman I was referring to that has more buzz.
Not really. Welling's name trended on Twitter the whole day he was announced to return. Plus, Routh is in a different position, because he was actually a bona fide movie star as Superman at one point, and Kingdom Come is, regrettably, very famous, iconic, and popular. To put it into further perspective, I run a Tumblr for Superman and Lois Lane and the posts I've made about Routh have received far fewer notes than those related to Welling and Durance. I think there's a lot of enthusiasm for both, which is lovely to see.
