Speaking from a player perspective, I honestly think the best option would be to delay the campaign for 3 months so everyone could play the way they wanted at launch, while releasing multiplayer as scheduled so everyone could play that in the mean time.
However, I know this won’t be the case. Even setting aside that they’ve stated they want the campaign and multiplayer to drop simultaneously, there’s just too many moving parts to constitute a delay. From a business point of view, the campaign is priced at $60 while the multiplayer is free. It just doesn’t make sense for the execs to pull the portion worth $60 from their holiday season lineup with the increase in sales during that time. On top of that, it’s also halo’s 20th anniversary, which they can really play up as a marketing ploy. Pulling the campaign during both the holidays and the anniversary would just be too detrimental to the bottom line.
And I get it, you can argue the game will suffer in the long run because of it. But that’s not how they’re going to see it. At the end of the day, it’s just too prime of a timeframe for Microsoft to ignore.