Well, when they've announced games earlier, several things happened.
1) they talked about features that they were working on, that ended up being scrapped due to various issues... which resulted in many people complaining about the devs being liars/the game is ruined/etc.
2) see this forum, and how it's picking apart every little detail they can find in a screenshot, making assumptions about everything that they can half-see in a screenshot, and then using those detail & assumptions to declare that the game is terrible/Beth svcks/Fallout is over/etc? Thats what the forums have been like for previous games, just for many more months. Led to a lot of anger.
Announcing closer to release is a good thing, overall.
...that said, there have been "features you'd like to see in upcoming Fallout games" threads in the general Fallout forums for years now. So, people have been able to suggest things (who knows how much they pay attention to those threads, of course.) Just not the folks who only came here after the FO4 announcement.