Design of Approaches using Vertical Guidance, where the minima is expressed as a DA/DH (and even RA), always takes into account the sink rate factor that's going to occur if the Decision is made to GA AT or ABV the DA/DH (MA not initiated after/BLW).
That is not correct. You cannot initiate a GA at the DA. A 50 foot momentary descent was already calculated in when the DA was set. The pilot must know their own sink rate and initiate accordingly to avoid going below the DA. For most ac, the momentary descent is far more than 50 feet, given response time, configuration, and thrust settings.