That is not accurate. The 4% withdrawal rate is based on the Trinity Study[1], which showed that it was unlikely to exhaust retirement funds over a 30 year retirement. It already includes compounding and draw down calculations.

There's a whole active debate around exactly what numbers are sufficiently safe over what time horizons and what portfolio mixes. For a fun long read, see ERN's series on safe withdrawal rates https://earlyretirementnow.com/safe-withdrawal-rate-series/

[1]: https://en.wikipedia.org/wiki/Trinity_study