Ask HN: Mainframe

Hi, I wanted to see what are peoples view about Mainframes and its future. I see alot of State, Federal and private banking companies are in need of Mainframe people due to alot of people that know how to do/run Mainframe are either retired or about to retire soon. Would learning Mainframe(either network side or software side) be a goood idea so that way you can take advantage of these companies looking for Mainframe people. I know its not a very specific question, I just wanted to see what people think out there about Mainframes.