These studios are changing the paradigm and going beyond the standard one and done, isolated universe , Superhero film model of the past 40 odd years.
Not saying that model is gone, but that now there's a new model which isn't bound to the same rules that the other model had.
You now have the concept of synergy between previous film and tv versions of characters and current film and tv versions of characters.
I think CW's Crisis on Infinite Earths , in particular, can be seen in retrospect, as sort of a sign post for the direction that the studios could take with these properties in particular. Regardless of what fans may think of that crossover, it was a signal to bigger plans moving forward.
That crossover officially broke down the barrier between past film and tv versions of characters and current film and tv versions of DC characters and said " They all coexist, and they're all canon". That was a big deal in the genre.
Marvel and Sony also appear to be taking that giant step in expanding the scope of the Marvel film canon beyond the films from 2008 to today.
It is something new, and it will be interesting to see if the three studios, WB, Disney, Sony, will be able to pull it off successfully.
I know there are fans who are resistant to this type of change and approach, but I find it very exciting and filled with alot of new story telling possibilities.