On: Classic PC demoscene productions running natively in the browser

[Sharlin]

But most people’s monitors don’t, or people just never set them outside the standard rate.

[ahartmetz → Sharlin]

My monitor's standard and actual rate is 165 Hz, which is probably not terrible at approximating 70 Hz (very few fps from a small multiple of 70 would be worst).

High fps is probably a little more rare than HiDPI, but also becoming more common. It's already common in phones.