It has nothing to do with open vs closed or "hacker" philosphy. See this the announcement of the closed Seedance 2.5 - https://news.ycombinator.com/item?id=49138302

Direct quote from the second top comment:

> Whenever I see the new releases around video generation (and image) generation models, I get goosebumps, because it just feels so fun to work with them.

Compare that with the launch of ChatGPT Image of yesterday.