The excel bit is likely because multi core support isn’t on Mac just yet. If you opt into their latest beta channel for updates, it gets way better.
Re:Hello, GitHub
by ponyfleisch on Tuesday June 05, 2018 @02:58AM
(#17235507)
No i had a different issue. I think it was after hard resets when excel goes "do you want me to restore the stuff i had open before?"
I would ignore this for a while (since plenty of other apps would also start up again) and then wonder what is eating my CPU. Surprise surprise, it's an Excel message box.
Skype on MacOS tends to get stuck in some loop that eats my CPU. So does MS Excel. MS Excel also had other, very annoying issues in the not so distant past.
Sure, as a MacOS user i'm maybe not that important to MSFT, but the quality of some of their products is surprisingly low.