I don't think you necessarily need to know about the IT aspect if you have enough knowledge in some of the other aspects of running the business. However, if you don't know the IT aspects, you should absolutely have a right hand person who is very familiar with the IT aspects and manages that and updates you on that side of things.
Musk has fired enough people who voiced criticism that I think he is only left with yes-men, not experts who can freely offer meaningful guidance and be taken seriously.
No. Mostly I turn off the notification stuff if I can, especially the little dot with the unread number. A lot of that stuff isn't worth reading.