Long-term investing is not a prediction about what markets will do next. It is a decision about what the portfolio should be able to do across many possible futures.
That requires more than diversification by ticker. It requires understanding how sources of return, liquidity, duration, and risk interact when conditions change.
Different jobs. One portfolio.
Credit may provide current income. Equities may provide long-term growth. Real assets may add cash flow and inflation sensitivity. The work is in deciding how those pieces should fit together for a particular investor.
A clear portfolio is not necessarily a simple one. It is one where each holding has a purpose and the overall structure can be explained in plain language.