>I don't pensions funds would invest in Start-UPs since they have a low risk threshold.
You seem to be mistaken. Here's a 2014 article titled "Behind the Venture Capital Boom: Public Pensions" from Bloomberg. Specifically, the article claims (sourcing a Dow Jones report) that "In 2014, they contributed 20 percent of the sector’s overall haul, down slightly from a 25 percent contribution in 2013." It's not that a massive fraction of each pension fund is in venture capital, but a sizable chunk of the money in venture capital is from pensions.
People who don't know COBOL, IBM Mainframe or the industry write these type of articles.
You want to loose the hardware - there's a solution for that.
You want to create modern web services over - there's a solution for that.
You want to code in a modern IDE - there's a solution for that.
If the systems that use IBM Mainframe were using Amazon ECS or Azure... the same people would write articles about the lack of reliability of core servers like banking and airlines.
You forget the old customers have credit contracts that last 50 years which have business rules, implemented in mainframe software, which no one understands or knows.
You can't migrate that way. An Insurance company can do that (contracts usually last 1 year) but Banks can't.
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