I'd understand if it didn't allow you to do multiplayer that way but I never do anyway.
I have gigabit internet, and I'm averaging 75 Mbit/s on this 85.6 GB update. At that speed, theoretically it would take just under 20 minutes to download. And I have the game installed on an WD Black NVMe, which can theoretically read/write at up to 3 GB/s.
And yet, I'm 90 minutes into installing, and I'm only 30% done.
What's really aggravating is that I bought the game through Steam. Steam was supposed to solve this bullshit of having to wait for patches to download by doing it automatically in the background.
It’s so bad that there is a meme I’ve seen which shows Steam claiming 55hrs of play time (when the game is open) and MSFS showing only seven hours of flight time.