With the whole celebration of Fallouts birthday which has been mostly looking into where it started with the original development team and various giveaways and other such like items a nugget was slipped into the roundup post (linked below) which confirms that a next generation update for Fallout 4 is coming in 2023 - so within the next year-ish!
Thankfully the game will not only be coming to Xbox Series consoles (S|X) and PC (Windows) but it will also be coming to Playstation 5, Microsoft not restricting the update to just its own devices/platforms.

It’s going to be a curious update as even on release Fallout 4 while being hugely enjoyable was not quite cutting edge in terms of visuals, that said while it is Bethesda doing the work, previous efforts from Microsoft (Halo graphical updates) have looked and played just as good as the originals so .. I can’t wait!
Bethesda wrote:Prepare for the future: A next-gen update is coming to Fallout 4! Coming in 2023, this free update will be available for Xbox Series X|S, PlayStation 5 and Windows PC systems, including performance mode features for high frame rates, quality features for 4K resolution gameplay and even bonus Creation Club content!
source: https://fallout.bethesda.net/en/article/jfwd8PsUw8r3pKrO1wOc5/fallout25-conclusion-interviews-events-perks