I see what you mean, but in this particular case, there are licenses that explicitly require the sort of attribution that the tweeter was asking for - e.g. the BSD license with the "advertising clause", or maybe the AGPL. For some reason, open source developers are choosing not to use these licenses, and complaining about it later.

If it were the case that AWS broke some unspoken social convention that is hard to legally enforce, I'd be more sympathetic. But it feels more like the author made a choice to license their software using Apache 2 over other licenses.