Remember that these were estimates from more than three years ago and before Microsoft completed its acquisition of ZeniMax in March 2021, so there’s always the chance that some of these plans have changed dramatically or been scrapped entirely. But they may provide an early look at some of the games we can look forward to from Microsoft down the road.
It’s not as critical for Bethesda’s series, because the stories don’t intertwine, but one good reason to update some series is that the games span a really long period of time, to the point where only players who grew up with the series will have played the whole thing. Otherwise, players can only play the later games in a series.