Also, you can't make plastics out of wind power or out of solar, you still need the "petro-" that's part of the petrochemical industry.

You can use solar to convert CO2 into syngas and do a Fischer-Tropsch synthesis followed by polymerization to get plastics.

This is false, you can make many plastics without fossil sources (pla, bio-pet, bio-abs, etc). The only challenge is cost and scale - it's cheaper and easier to use existing processes.

But making plastics using renewable energy and fossil hydrocarbons for feedstock does not exacerbate the greenhouse effect, unless you burn them when you've finished with them.

Arguably plastics are a stable, cheap and useful carbon sink and if climate is the overriding ecological priority we should be making as many as we can and recycling as few as possible.

You can make plastics out of cellulose, which is available from plant sources or organic (algae) bioreactors.

It would take a while to retool the plastics industry to use organic sources, but it's not at all impossible.

Plastic packaging can be substituted. Engineered plastics are a tiny fraction of petroleum.

Using renewables means you're burning up less of your plastic feedstocks.