The way I see it is we may have mods like SKSE, Unofficial Skyrim Patch (since these are both worked on by groups of people) and MAYBE ENB come back. However, other individuals that created the mods for the Skyrim: Legendary Edition are the ones that are of concern. Heavily Endorsed mods may have a chance of coming back, but the Gems that are less known are on the verge of being lost until someone stumbles upon or has known of the previous mod, becomes inspired, and builds a redux. However, even that is not certain. Going to be interesting to see what happens.