At typically more than 2x the cost. I've played Alyx on both, the Index is absolutely not a 2x better experience.
I'm no fan of their corporate parent either, but the value proposition on Quest 2 for general purpose PC VR gaming (especially prior to this price increase) was remarkable given size of subsidy Meta were prepared to make on price.
It's a bit baffling that the Index is still as expensive as it is, it's three years old and has never gone on sale even once nevermind had a permanent price cut. In a vacuum it's worth what people are willing to pay, but Valve are a software company selling hardware to promote their ecosystem, which they're ceding to the much more affordable Oculus ecosystem by keeping the premium price.
It's still a nice headset but it's showing it's age, the Quest 2 has higher resolution screens and the ability to stream PC VR wirelessly is a killer feature which the Index doesn't support.
I'm no fan of their corporate parent either, but the value proposition on Quest 2 for general purpose PC VR gaming (especially prior to this price increase) was remarkable given size of subsidy Meta were prepared to make on price.