An H9 has more than twice the power of a DSP4000, so it's no slouch.  Each of its algorithms is in  effect made up of what would be multiple algs on an earlier box. Example pitchshift+reverb+dynamics+eq etc.

We tend to  prefer one big alg to two or more little ones, partly because they sound better, and also because on a 2 switch guitar pedal it would be very hard to usefully control multiple algs – many people already consider our boxes complex and difficult to use. 

An H9 may have the power of a rack unit, but it is NOT a rack unit. Horses for courses.