Perhaps we have different ideas of what constitutes "buttery smooth". I find the performance usable but sluggish. I think many people have become accustomed to this kind of performance though. Regardless, I find the design of the UI quite appealing.
AMD® Ryzen 9 5950x, 32 GB RAM, Linux/Fedora 35, Firefox 97.0, Chromium 96.0.4664.110