A proper surround setup (5.1 is more than enough for a mid-size room) or even Atmos speakers can be had for a reasonable price if you shop around. There's really no substitute (in my opinion) for the experience if you watch movies and have a compatible receiver/amplifier. A large and well-designed subwoofer is incredibly noticeable as well depending on your use case. It can easily sound better than the large majority of seats in your average theater which aren't ideally positioned without spending too much.
If all I did was watch Micheal Bay movies I guess I would agree. I have a very nice amp and speaker setup hooked up to my TV. It sounds fantastic.
I never turn it on, I use my TV speakers. Even with cinematic shows I find they mix the dynamic range so high that it's insufferably loud when something exciting happens, and then I can't hear anyone talk for the rest of the show. I'm constantly changing the volume.
