They keep failing because they keep creating integrated "modeling amp" products which put the original amount of wattage in the back end, and that destroys the model at volume: you start hearing the break up of the back-end amplifier.
They are doing that to save costs: real tube amplifiers continue to be posed as higher end at higher prices.
A decently modeling amplifier would probably need several hundred watts, if not into the thousands, just to replicate a 50W tube combo at volume. The speaker cabinet and drivers would have to be different: high fidelity units, not guitar speakers.
I think people do get good results when they plug their modern amp modeling digital signal processors directly into a loud PA system, where the models find a decent amount of headroom and fidelity to reproduce what they are doing at loud volume.
They are doing that to save costs: real tube amplifiers continue to be posed as higher end at higher prices.
A decently modeling amplifier would probably need several hundred watts, if not into the thousands, just to replicate a 50W tube combo at volume. The speaker cabinet and drivers would have to be different: high fidelity units, not guitar speakers.
I think people do get good results when they plug their modern amp modeling digital signal processors directly into a loud PA system, where the models find a decent amount of headroom and fidelity to reproduce what they are doing at loud volume.