Have we? Or have we just seen campaigns and legislation against plastic straws and supermarket bags, which amounts to mere virtue signalling and greenwashing by corporations and governments?
We need to do much better than ban plastic straws and advertise how we've saved the world. Properly pricing in externalities onto the price of single use plastics would probably go a long way to motivate the market to give a shit.
Now the funny thing is that you get to see other families' trash bags once a week on their front door and there are big differences. My family has a tiny yellow bag every week and a blue one every other week whereas many others (with comparable family sizes) have 2 yellows at least and 1 blue every single week.
My guess is that they eat a lot of food coming from the supermarket: lots of wrapping, lots of cans, etc. It's an informed guess because the blue bags are transparent :-)
Of course we should be reducing plastic waste, and at least where I live, I've seen a big push for the reduction of of single use plastics, both through legislation, savvy consumers and responsible supermarkets.
While the biologists work on plastic-eating enzymes, product engineers can work on sustainable packaging, logistics specialists can work on low carbon distribution and politicians can work on ensuring economic motives align with a positive future for our planet.
There is hope.