I’m very happy knowing you used the search. That means you already know that nobody ever complaining follows up on the issue. And you know what that means…: They’re now all either dead or trapped in an alternate dimension. Or… You know: Lazy.
On a more serious note though: It’s always isolated cases with this issue. I’m guessing that in these cases have some sort of local cause. Like their setup having a bad day, or the provider acting up, or the FBI working overtime on their wire…
All I can tell you is: Compare the speed to other sites hosted in the same country as itch.io and restart your router to get a new IP. If that doesn’t work, ask your provider for help. After all: You’re paying them a pretty penny so stuff like that doesn’t happen - and other users can download from itch just fine.
The “at work” issue I can’t help with. Might be the same provider… Might be your boss(es) putting a limit on download speeds… Might be Janine from IT, who’s still grumpy at you and uses this to get you to walk over to her desk, so you can talk it out outside of her break time. Working environments are too complicated to diagnose by guessing.
But if the assassins didn’t get you by the end of next week let us know about your progress.