Also, if you go for measures like mass processed, the weight of microchips, pcbs, parts is only a tiny fraction of what has to be processed and build in the supply chain.
Agreed that it is smarter to use oil for plastics then to burn it directly.
My argument is that as long as we are still burning oil and gas, we might as well burn old plastic instead of new oil and gas.
If/when we stop burning oil and gas, then we can think more seriously about recycling plastic.
1) Plastic is not liquid, so you can't pipe it to a gas or oil power plant. You may argue that coal isn't liquid either, but continue reading...
2) Burning plastic generates toxic fumes.
3) Plastic ash is sticky and very difficult to clean.
It's a fascinating topic. There's even more problems than the ones you bring up, but engineers are also pretty smart.
The world has effectively infinite resources, getting more is usually just a matter of figuring out better extraction techniques or using better energy.
Sure, like effectively infinite atmospheric carbon sink, effectively infinite Helium, effectively infinite fresh water, effectively infinite trees ... we've treated these things as true, because the World is big and population of humans wasn't so big we've got away with that for a time, now those presumptions are coming to bite us, hard.
Yes, we can work our way out of some holes, maybe all of them. But we have to make things sustainable first, then spend those resources. We're not wizards, deus ex machina only reliably happens in movies.
A little Malthusian.
For example at 1% energy growth per year it would only take around 9-10k years before to reach an annual consumption equal to all the energy in the Milky Way galaxy. By "all the energy" I don't just mean consuming all the solar energy from all the stars, and using all the fissionable material in reactors, and fusing everything that can fuse, and burning all the burnable stuff. No, I mean also using all the gravitational potential energy in the galaxy, and somehow turning everything that has mass into energy according to E=mc^2.
From there at 1% annual growth it is only another 2-3k years to using all the energy in the whole observable universe annually.
Population at 1% growth also gets out of hand surprisingly quickly. If we don't get FTL travel then in about 12k years we run out space. That's because in 12k years with no FTL we can only expand into a spherical region of space 12k lightyears in radius. At 1% annual growth from the current population in 12k years the volume of humans would be more than fits in the sphere--and that's assuming we can pack humans so there is no wasted space.
We actually have population growth under 1% now, down to around 0.85%, but that only gets us another 2-3k years.
The World has limited resources, we don't have a spare.
Do you need it spelling out more clearly?