And the way WotC is running... You wouldn't be writing the DMG.
They're leaning -hard- into online play and online spaces. Not just Roll20 or Talespire or whatever else. They've repeatedly looked into making their own online TTRPG platform for playing D&D across the world. Why?
Because it breaks down one of the greatest blocks to gaming in any TTRPG space there is:
Splitting the Playerbase.
Just like MMORPGs you want as many people buying and playing your game as possible when you're a TTRPG publisher. You want every possible block out of the way. And learning from MMORPGS is also super important. Look at what World of Warcraft has been doing for two decades, now, as it refines it's process.
It started out with a hard faction break, which resulted in a ton of servers leaning hard Horde or hard Alliance because people wanted to be able to do raids and stuff and if there's not enough Alliance players online when you can raid you rolled up a Horde character to go where the people were. They didn't recognize the problem so they allowed players to faction-change their characters for a fee to make some money off of it and give people a shortcut rather than having to re-level and re-gear the whole way up.
But if you keep that trend going for 6 years and suddenly you've got servers that are so one-sided the PvP community can't even do a Battleground because there's not enough of the other team to play against.
So they started bulking up the capabilities of their servers and then consolidating. Now instead of 10,000 active users the server could handle 20,000 active users and they combined a Horde-Heavy and an Alliance-Heavy server. And it worked great! Kinda.
Because people aged out of WoW. People got snagged by other games. People literally died and entire raid groups would break apart because the raid leader was in a car accident or had cancer or whatever else. And the server would start slanting, again, and keep going because people are gonna people.
So they started making cross-server play functionality. Now you queue for a battleground and you get players from 10 different servers on your team! Which helped a lot, but there were still issues.
So they keep introducing new fixes and mechanical support. Like cross-faction teaming and cross-server guilds and more, so the faction divide doesn't matter as much anymore. They installed this pointless barrier to try and instill brand loyalty to a red or blue banner and it caused SO MANY PROBLEMS over the years. You know what else caused problems?
Doubled Zones. Back in Vanilla through Cataclysm you had tons of options for where to level. You wanna hit Northrend? Cool. Borean Tundra or Howling Fjords as your point of entry? Sure it made spawn-timers easy enough to manage as players hit either side of the map, but the amount of effort and time spent on game design didn't translate into doubled leveling time. You finished Howling Fjord and didn't need to do Borean Tundra because it was lower level.
So now every expansion is a pretty tight path of leveling through selected zones. There's no doubled-up leveling zones, anymore. Everyone goes through every zone so they all play in the same space and populate the same world!
You can map these same sorts of problems to TSR and WotC!
TSR created tons of material! You had Dragonlance, Dark Sun, Ravenloft, Forgotten Realms, Greyhawk, and more settings out there for a lot of narrative variety. BUT.
If you wanted to play Dark Sun and no one in the area was running a Dark Sun game you were SoL. Lord knows I often was as a teen in the 90s. Oh, sure, there were Dragonlance and Ravenloft games at the FLGSs I could get a ride to, and I played in them, but I had an Athasian Thri-Kreen Psychic Warrior I wanted to play and never could. You know?
WotC discontinued a -bunch- of Campaign Settings when they took over. They spun off Ravenloft to Sword and Sorcery to let them muck around with it. It's not that those books didn't sell at all, it's what they split the playerbase. Spread people out across the Howling Fjord and the Borean Tundra so they were playing the game but not together.
Online Tabletop? That will kill the Faction Divide. We have the technology to make sure a teen in Georgia can find a Dark Sun group out in the great wide world even if there's no one running that setting at their FLGS.
WotC is going to lean so hard on that that the "Playing with your home-table friendgroup" advice won't be in future books. You're already friends with them. You know them and you deal with them on the regular. You don't -need- advice on how to get to know them and work within their boundaries that you likely share because you're already friends.
But when you're playing online with a friend in China and you start sprinkling skeletons and ghosts onto the battlefield you need to know that they're considered especially unlucky and gross. Like far beyond the desensitized Western view of undead as "Generally acceptable levels of creepy".
Again, something we can learn from World of Warcraft who made their undead Forsaken look like the left in the US and the right in China.
Because at the online table you need to take into account the feelings of people you don't know terribly well. And for those kinds of games?
Safety Tools are an outright godsend.