[Maybestring]

It is absolutely true that 'the rocket equation' doesn't account for thrust. It also doesn't account for gravity gradients, aerodynamic drag, relativity, solar wind, the cosmological constant...

It's very accurate when those things contribute little, and totally inadequate for modeling spaceflight if any are significant.

There are more complex versions that account for those things, but 'the rocket equation' is always understood to mean Tsiolkovsky's equation.