I heard about something that happened some time ago where a man won a huge some of money in gambling and he decided to save the money in a particular bank the money was there and later on the bank was closed down and he had to go through a lot of procedures to get his own money he was paid half of the money with promise of completing the payment soon, this won't happen if you saved with Bitcoin.
I don't know where you are from but every country has different banking laws, it is impossible for customers in my country to experience this even though there are quite a lot of banking scandals such as hacking that make customers lose money.
From the cases you mentioned, it is indeed very unfortunate but it is not a guarantee that if you save Bitcoin you will not experience loss.
You read and hear how someone lost their bitcoin on an exchange because the exchange was hacked, or their wallet was hacked because they did not save it properly or because they just clicked on a link that contained a virus and other dangerous things, so saving in Bitcoin is very good but it does not mean that Bitcoin solves all the problems that occur in the cases you mentioned.