We need to get out of our parochial ideas about waste. Plastics are aesthetically bad, but other forces are quantitatively way worse.
I don't agree with this line of reasoning. We have room for more than one priority, and solving the waste pipeline is ultimately one of logistics and political will, as well as elbow grease and the pluck to get out there and pick up some garbage.
I've seen whole gaggles of people walk past a bottle lying on the ground next to a trash can, and no one would stoop over and pick it up and put it in the trash. Humans have this disease on societal scales, and the oceans are taking hell because of it.
Don't let a few assholes be a surrogate for justifiable outrage that comes from a completely different source on an incomprehensibly massive scale.
Oh I'm well acquainted with the problems in developing countries and they are disproportionately responsible for the state of the oceans. However, I'd say that they are all just degrees of the same problem. I've picked up lots of trash in developing countries, but also plenty along American highways, even in the most scenic areas of the country, and even seen it here and there even in the cleanest countries (Japan, Switzerland, Germany). I met some really nice people all over New Zealand who as volunteers simply go out and pick up garbage off the beach, in the bushes, trees, rivers, whereever it occurs. They recognize other places are shitholes but that doesn't stop them from doing something about the trash where they live. If you join in, in short order you can't help but realize that it isn't all washing up from some shithole in Southeast Asia, but a lot of it comes from local sources. Litter and dumping are universal problems.
Don't fall prey to the "solving the biggest problem first" fallacy. Yes, we need to fix the pipeline and help those countries develop waste management systems, we need to stop producing so much plastic, but hell, when there is trash laying around, just pick it up! Getting people involved in doing this is the best way for them to see that this is a widespread problem, not just some trashy fuckwits over there that we can blame it all on.
In many parts of the ocean we are way past aesthetics.
73% of Deep-Sea Fish Have Ingested Plastic: > https://www.ecowatch.com/plastics-deep-sea-fish-2536726086.h...
Whale Died Of Starvation After Eating 80 Plastic Bags Off Thailand's Coast: > https://www.forbes.com/sites/trevornace/2018/06/04/whale-die...
All UK mussels contain plastic and other contaminants, study finds: > https://www.independent.co.uk/environment/mussels-plastic-mi...