(Bloomberg) -- Apollo Global Management Inc. Chief Executive Officer Marc Rowan rejected the notion that adding private assets to retirement and insurance portfolios can pose a systemic risk, calling concerns about such holdings overblown.Most private credit held by insurers and pension fund buyers is rated investment grade, the CEO told investors Monday, pushing back on the idea that the asset class is less transparent than traditional loans. Lenders can get direct access to borrowers’ management, he said. ...