This is the kind of criticism that could only come from someone without much formal writing experience.

This is a very normal workflow: You write a full-length text detailing the project you worked on. You then trim it down to a summary which you share with a group of people X. You then trim it down into a different summary which you share with a group of people Y.

When you do this multiple times you unsurprisingly end up with some sentences that make it into multiple summaries because they're that important to the thesis!

(Also, the summaries on Twitter and Reddit aren't anything close to "most of the writeup"—the full text is 6000+ words!)

So you agree this is a formally written PR piece copy-pasted and as such it's spam. Got it.

What would've been not spam? Spontaneous writing with a link to the puff piece.

I'd rather some company copy&paste the same text multiple places -- if the alternative was that those places would instead get obfuscation of the same information to appear novel each time (so I'd have to read all of them to realize they're all just the same info).

I dont inderstand your issue with this. Is it that they share their work several places, or that they don't describe their work in an unique way every time?

i prefer this, to the story about that time they went to Florence and their grandma made pizza for dinner and they got the recipe.

Eh, seems like legit marketing to me. Yes, they are trying to sell you something, but they are doing that by releasing non-trivial research and open source code.

The same company reports multiple times on a finding they've made through multiple social media channels? Shocking. /s