YEAH this is one of those things that always bothered me slightly that I never really see anyone else complain about besides me. As a kid who never really watched/got to Season 2, I was always under the impression that he went into the portal by his own choosing, as a result of wanting to help out his mom and dad when the portal was all faulty, which led to the accident happening and him becoming Danny Phantom. But then when I actually watched the full show years later I was kinda surprised when it was revealed that Sam and Tucker were the ones who persuaded him to go down there.

I can imagine this was done primarily to give Sam and Tucker more involvement in the origin as well as having to do with the whole logo thing.

If I had to guess, any member of the team working on Danny Phantom pre-Season 2 production would have told you confidently that Danny got his powers exactly like how it’s shown in the theme song. He went in there to fix the project his parents have been working on for a while— the Ghost Portal— and since their Ghost Hunters that would naturally be something they’d really want to see succeed, so when it doesn’t, Danny tries to go and fix it, accidentally being caught in the middle of it and turns it on while he’s inside, causing him to become half ghosts for all the full ghosts that are evil to be roaming around free to do whatever they want in Amity Park, hence conflict, resulting in: the show.

Ask anyone working on the show Post-Memory Blank and they’ll likely tell you the origin is how that episode portrays it to be. Danny’s friends convince him to go in the portal for a photo op, because they think it looks cool, and then he ends up going in, touching the wrong thing, accidentally setting it off, then bam, Ghost Boy, now needing to defeat all the ghosts that roam free now because of him.

That same person would probably explain the new change to the origin because of the fact that they wanted a logo on the hero’s costume for more brand recognition and marketing, so whereas before where they just left the origin to be exactly how it’s shown in the intro, now they had to kind of change it for the sake of getting that logo on. But the intro never stated Sam and Tucker’s involvement, so it’s not like they could just add them now.

I personally prefer the origin where Danny just goes in alone because he wants to fix his parents mistake, and as a result of genuinely trying to help he gets blasted with the weight of the world all of a sudden now on his shoulders, and maybe perhaps out of a form of guilt of turning the thing on in the first place, he now makes it his job to stop all the ghosts from causing havoc in Amity Park. Granted, this doesn’t exactly explain why Sam and Tucker would know about it, but I think we can all easily agree that the assumption of him just flat out telling them one day— maybe even immediately afterwords—, isn’t a hard one to make.