It's things like this (and opposition to nuclear, and refusal to consider geoengineering) that make people skeptical of the general environmental movement. After all, if this was such a huge problem... People would be trying to actually solve it instead of virtue signalling.
As for 'the plastic straw wins', I'm unconvinced. The energy cost might be lower, but none of your other reasons factor in environmental cost at all. I don't think any amount of 'feels good' is worth any amount of environmental damage.
Lastly, even if it were entirely symbolic (which it isn't) there's still value in that.
That said, this article is one of the few that really changed my perception. I admit that I have released many balloons over the years, joyfully, with the assumption that latex biodegrades. Now that I see how empirically dangerous they are to seabirds, I won't be so joyful and will surely share the facts instead of releasing the balloons.
If you care about it, talk about it in the context of fishing, don't just bring it up as a way to snarkily shut down people doing something good, no matter how small.
This is exactly the kind of "plausible deniability" tactics that people who actively push to disregard all environmental concerns use.