"While we have nothing to announce today, please know that the PC community is very important to us and top of mind as we work towards the future.”
This being MS, who have teased Halo on PC for years, which I don't believe much in. They haven't done much in terms of ramping up the Windows store to being on Steam's level, as well as being very supportive of the modding community (which they've struck out against recently).
Even if they do decide to put Halo on PC, it'll only be through the Win 10 store and it'll be restrictive as hell, as well as being sold at a higher price, despite the collection already being 4 years old.
If the PC community was really that important to you, you would have already taken plenty of action to prove that statement MS.