As someone who has played a decent amount of Destiny 1 & 2 all I can say is I can't wait... to hear about loot and progression on the 13th.

The core gameplay loop is going to play a huge part in how people percieve this game. Is the campaign the main source of content? Will there be activities similar to strikes or raids? How much larger is the map from what we played? With random rolls on the weapons we already know that content will be replayable in some form, the question is exactly what you'll be replaying.

People can forgive a bad campaign if what comes after is what makes up for the majority of playtime, that's how Destiny has been doing it since D1 vanilla, and with their most recent release they even shaved off the campaign content. Altough D2 personally isn't a great example of how things should be done, especially right now with Black Armory.