A lot of digg submissions were "stolen" from reddit even before reddit got big. Thats how i found out about reddit. Content is king and reddit had better content than digg from the start. Fediverse cant compete with reddit in terms of content atm.
This whole "reddit will die just like digg" sounds like copium to me. I am boycotting reddit but we need to be realistic about the situation. I am not even sure the fediverse(or its members) can even handle reddit's traffic, on an architectural level. Reddit will eventually die but it wont be as fast as digg. And even digg lasted many years with decent popularity.