I'll bet there are license restrictions or tax advantages to staying under 500cc in India. Lots of 400 - 450cc machines built there though.
The counterbalanced 390 KTM and 452 RE motors both make around 40-45 HP and have 6 speeds. They are 50 - 150 pounds lighter than the RE 650s. The old RE 500s were 22 - 28 HP machines with 4 or 5 speed gearboxes. The new LC452 in any of its upcoming guises could run off and leave one for dead. The Scram 452 will likely be a hoot. The trad-looking OHC Chinese Benelli Imperiale 400 single also comes in a 460cc (AKA "500") version, and that depends on where you live. With modern engine tech, a 450 thumper is plenty fast. Add a "500" decal and nobody would be the wiser.
The Bigger Imperiale Shown At India Bike Week 2022 | QJ Motor SRC 500 Walkaround Video
https://www.youtube.com/watch?v=V-w6yGqdZak