I don't think this is right. If you look through the content, all of the channel ids, countdowns, breakfiller and titles are full frame 4:3, whereas the titles for the news itself are 14:9 hard masked. Which implies that although the newsroom was being shot in 16:9, it was hard masked to 14:9 in the gallery, and all of the titles were produced to already reflect this format.
It seems unlikely they would have produced the channel content in anything other than 4:3.
Somewhere at Lambie Nairn or maybe even at the BBC there were probably widescreen masters of the news titles content, as it makes sense that they were originally created in 16:9 with a 14:9 safe. It seems very Lambie-Nairn to have produced them in 16:9, ready to be compatible when the channel finally threw off the shackles of the 14:9 compromise, not imagining that their gorgeous branding would be retired only a few years later. Similarly their rebrand in 2008 was done entirely (I assume?) in HD, so the move to Broadcasting House didn't require much work with the original assets.
Again one of the issues is the only footage we have of BBC World in that era in widescreen dates from the TVC
bomb, and the TVC powercut. Both of which involved lashing up a temporary setup at source, and again are recorded on VHS or more primitive capture cards. So the fact these clips are aspect ratio bingo is more likely a result of the odd situations.
ISTR that BBC World had a traditional presentation suite whereas News 24 was just all done though its own gallery. So it would make sense that the pres suite ran in 4:3 and took the 16:9 feed from the N9 gallery and cropped it to 14:9 letterbox for broadcast. So therefore if the laserdisks were made for day to day use in the pres suite, rather than being the originals Nambie Lairn created or delivered, they'd be 4:3...
*BUT* the sports stings etc would be being used in the gallery not the pres suite. And that gallery was definitely 16:9 capable as it was the old News 24 gallery from launch, and was producing overnights and BBC Four News in 16:9. So why are they are on the laserdisks for pres? Redundancy perhaps but 16:9 versions of at least the news assets would have had to exist in the gallery.