No, your receiver isn’t junk if it doesn’t have Dolby Atmos
The modern audio format that everybody, including myself, is raving about is Dolby Atmos. It’s directional-based audio, and if you have a proper system for it, then you should be able to hear things like overhead gunshots or planes in your movies, and it’s a truly immersive experience. I went out of my way to build an Atmos setup, and I don’t regret anything about it. I use it daily, and while I don’t use the Atmos part of it while watching regular TV, I watch enough movies to make it more than worth it.