Possibly true, but it ..... kinda did with Axe III Fx vs II.
When I bought my Kemper, it was head to head with the Axe II Fx where I considered the Kemper to be superior (we are talking a couple of days with friends doing a shootout). A single afternoon a few years later with the Axe III Fx, and even right out the gate, I felt it was fairly even with Fractal taking the lead in EFX due to the new models and new efx in the Axe III.
I agree with others here that things have gotten SO good that it is now quite difficult to have a groundbreaking new modeler based on sound quality. I would go so far to say that those days are over forever.
Stadium's real chance to shine IMO is in workflow. Fractal IMO is still cumbersome to get a specific tone you want out of it compared to Helix (and Kemper IMO). Stadium has the hardware to support more substantial efx than Helix original ever could (this is especially true for reverbs IMO). I would have at least added better delay and reverb engines at release.
Still, the thing is beautiful. The workflow and GUI are groundbreaking. I also think that as many here have said, we are all just hoping to be "wow"ed and that is getting increasingly difficult to do

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