Sulu as Captain

[Therin of Andor]

But he really wasn’t much a part of TUC. You get the impression his scenes were probably all been shot in a day or two at most and he barely gets to interact in person with the rest of the cast. So, it’s a double edged sword.

Following some previous fan support, George and Grace started lobbying at conventions for a "Captain Sulu" series. They weren't taken very seriously, but it did inevitably lead to "Flashback", an episode of "Voyager" that recreated and extended their ST VI bridge scenes, brought back several ST VI supporting actors and extras, and put Tuvok onto the Excelsior's bridge.

 

[Maurice]

Or the writers remembered Sulu and Rand on the Excelsior from Star Trek VI and it had nothing to do with that Sulu silliness.

 

[Allyn Gibson]

Or the writers remembered Sulu and Rand on the Excelsior from Star Trek VI and it had nothing to do with that Sulu silliness.

This. I very much doubt that George Takei lobbying for a series of his own had any effect on the Voyager writer's room doing a 30th-anniversary episode.