Which is Better?: Risk Free Rate vs SPY during high Inflation rate period

With the current inflation rate of over 4% and sustained for over a year already, is it better to just invest on fixed income high yield instruments or invest in SPY for the long term?

Below is my compiled list of annual inflation rate, fed rate, and spy performance for the years 1968-1985 where inflation rate was sustained at 3% and above.

Had you invested $1,000 at the start of 1968, the amount would have grown to $4,363 at the end of 1985 if invested in the "risk free" Fed rate. It would have grown to $2662 if invested in SPY during the same period.

From the graph above, we can conclude that investing in the risk free rate during the high inflation period is more beneficial than investing in the S&P 500 ETF SPY. In addition to its superior performance (compared to SPY), it also has no drawdowns and stable / steady returns.