Modding is a totally underrated thing right now, but I feel it might become big in the future. Someone just needs to come up with a solution to both keep mods free and incentivize mod authors.
The way I see it, the big boys create games that acts as platforms and users freely create content of their own using these platforms. Bethesda/Microsoft might be in a good position to achieve this, they have good modding communities around their other games, really interested what their next title brings to the table, hope they don't blow it up like the last time they tried to monetize mods.
You also have something like Roblox, where the concepts of game development and modding kinda blend together, so it's definitely a trend to keep an eye on in the future.
You should keep an eye out for S&Box! It's the successor to the popular Garry's Mod.
Garry's Mod is, imo, the sandbox and modding game and I think that S&Box will be even better. It's based on the Source 2 engine, and the main developer Garry has collected a lot of experience with GMod.
While GMod mods are based on Lua, S&Box uses C#, which is an awesome choice, imo. C# is a bit more verbose than Lua, but it probably enables mods of higher quality.
It's not out yet, but some keys get distributed to chosen people. Sadly, I'm not one of those.
The way I see it, the big boys create games that acts as platforms and users freely create content of their own using these platforms. Bethesda/Microsoft might be in a good position to achieve this, they have good modding communities around their other games, really interested what their next title brings to the table, hope they don't blow it up like the last time they tried to monetize mods.
You also have something like Roblox, where the concepts of game development and modding kinda blend together, so it's definitely a trend to keep an eye on in the future.