1. is never happening. If you want a proper safe car seat for a 1-3 year old, it's going to weigh 30-40 lbs no matter what sintered pixie dust you build it from. And it has to be pretty huge since a small person has to fit almost inside it.
Even the ones for babies, that people for some reason I can't fathom like to carry around in the supermarket, are actually also 20+ lbs, you've just left 15 lbs remaining in the car occupying a seat while you're shopping. And they're also bulky.
2. could happen for children aged 4+ in a minivan-sized car. I've already seen it on some long distance buses. For younger kids however, they really need to sit facing rearward, but also must be well protect against side impacts, so it's very tricky to make something retractable that doesn't take a huge amount of space.
Even the ones for babies, that people for some reason I can't fathom like to carry around in the supermarket, are actually also 20+ lbs, you've just left 15 lbs remaining in the car occupying a seat while you're shopping. And they're also bulky.
2. could happen for children aged 4+ in a minivan-sized car. I've already seen it on some long distance buses. For younger kids however, they really need to sit facing rearward, but also must be well protect against side impacts, so it's very tricky to make something retractable that doesn't take a huge amount of space.