I think game engines receive all kind of features and fixes all the time. Some of it are of course requested by users too. It’s the “when it get’s done” that defines whether it was done due to public interest or internal reasons. As far as the “when it get’s done” goes here I think the delays indicate usually features and fixes are done only when there is enough internal interest. Like the scale variation for grass node requested by a large audience by the time of 4.8, implemented with 4.12.
That being said, I don’t think forward shading support is back on track because it has 601 votes and a lot of community interest behind it. Because at the same time Volumetrics are canned with 576 votes. And instead we see things on the to-do list such as Multiple Skylight Bounces with 7 votes. The votes seem to be a trello that are there, not necessarily Epics intention of letting people vote for features.