On which part? When it comes to Y2K being a real problem, my dad was working at PepsiCo at the time. He had to spend a lot of time and effort upgrading or replacing a lot of their systems because they would have stopped working and/or had major database issues if the time bug hadn't been fixed. On top of that, a lot of backend systems were (and probably still are) designed to be running 24/7. The result is that it can take a while to get systems back online if one of them goes down unexpectedly. If all of the systems had gone down at the same time, it would have likely resulted in a catastrophic failure that could have bankrupted the company.

From the standpoint of corporations spreading misinformation about Y2K, I don't have any concrete specifics, however my dad's mentioned that his manager afterwards had warned the team he was on that there were grumblings from upper management and executives about Y2K preparations being a waste of money. Afaik nothing ever came of it inside the company (or if it did, it didn't effect my dad), but it seems odd how easily the "Y2K was a hoax" conspiracy theory took off (I'm almost certain I've read a few articles about CEOs spreading misinformation about it shortly after the event, however I haven't been able to find anything with a quick Google search).

As for Y2K being taught as a hoax... look around you. How many people do you think believe it was a hoax? Whenever I hear about it come up, it's people ridiculing the "doomsday cult" that was pushing for corporate and government entities to fix the bug and how unnecessary it supposedly was. Someone is teaching them that, whether it's formal education or informally via peers or the internet.