I was referring to VHS recording which is limited to less-than-broadcast resolutions.

DVD and HDD PVRs for analog broadcasts did capture at 480i but were wildly expensive.

Subchannels are an interesting concept, but suffer from compression loss from packing in multiple streams into a single 6 MHz slice that would otherwise be a single channel.

Don’t get me started on the fact that we are limited at 1080i as well.