It was ok. For a game fans have been wanting since the 3rd Streets of Rage 25 or so years ago, I feel there wasn't much to it.
In my opinion, The game didn't pay much homage to the older games and that can be good or bad. If I think back to the last games, There were a lot of levels or soundtracks that stood out. With Streets of Rage 4 all the levels seem to blend into one, a few stand out but they all share the same dull gritty nature. The music is bland and generic, With a few paying tribute to soundtrack from the original games. The end of the game just cuts off seemingly with no real ending.
As for the gameplay it seems to have gone back to Streets of Rage 2. No running or side rolling. However with the new enemies that can throw items or track. Watching your character try to slowly move out the way can feel like a pain.
However, Not all bad. It was definitely fun to play and offers good replay value. There are some fun new characters and enemy designs. And some new modes thrown into the mix aswell