It's absolutely essential (along with LightRoom), especially if you shoot in Camera RAW, which is essentially the digital equivalent of a negative. For my nature, landscape and architecture shots, I don't change photo elements other than removing spots from dust on the lens or the odd power line. For my "artistic" shots, like the coloured glass or the colours on the bike, I'll play with the image.
Because the RAW files have all the information that the sensor collects, they tend to be washed out and flat. I do all the work manually that the camera does when it saves as a .jpg based on the presets in the camera. I'd rather control the image processing and output rather than use what some engineer at Canon or Nikon etc decided the settings should be
Photoshop is not a bad thing, in fact it's quite the opposite. It's a problem when photographers or advertisers pass off unreality as reality, or make hilarious mistakes. That's where the term "Photoshopped" became a verb for making a stupid or bad edit on a photo. It's like any other tool. A hammer can build a house or smash a window.