Yes that is true!
Siril is built to do stacking of many frames accurately which is just what is needed.
This is also why HDR is best done by Siril. If you shoot at one exposure, then the sensor will clip off the very highest exposures (when the sensor well is full of electrons).
Basically, the sensor is only good at the math of adding up photons within the limited range where it is linear - outside that it clips.
If instead you take multiple exposures at different exposure values then multiply them by factors, (i.e. the weighted average) and do the combination in Siril with 32 bit floating point math it will work for a much larger range at values.