This question came to me as a comment on the bomberman wiki. They are technically the same character aren't they? I wanted to ask some seasoned bomberman fans before I make such an update.

If said question is true, then would bookworm green be the same as green bomber and the same for giant gold / gold bomber? Discuss.

Hard to say. A lot of the Land characters do seem to be derivatives of characters from the original series. But they also have distinctly different personalities, designs, and names. The original colored Bombermen are mostly just palette-swaps without any characterization.

Not to mention that the Bakugaiden anime also features the colored Bombermen in its cast, and they're clearly not the same characters, or at least, not from the same universe. For example:

Gold Bomberman: Just another Battle Mode competitor.
Giant Gold (Land): Cheerful White's rival and leader of Team Gold.
Golden Bomber (Bakugaiden): White Bomber's father.

Another example would be how Red Bomberman is a male Bomberman in the main series, his counterpart in Bakugaiden, also named Red Bomber, is a female.

So in a sense, they're all the same character, but only in the way that three different Robins (from Batman) can be the same character. Whether or not they need to be merged into single pages really depends on how much information there is on each character, in my opinion. If you ask me, I would say to keep the pages for the Land characters as they are, allowing more info to be added to them, and consolidate the colored Bombermen's pages all into one page, because there's really not anything to say about them other than they are traditional Battle Mode flavors and some of them have appeared as Black Bomberman's sub-bosses or as caged allies. (So like, a page for White Bomberman, a page for Black Bomberman, and then a page called Colored Bombermen or something of the sort)

Except perhaps Gold Bomberman, who is distinguishable from the rest as an unlockable character (SB5), and a character who uses a special ability (Neo Bomberman), as well as being a "prize" in most Battle Modes.

Just throwing out ideas here.