Soundbar Vs Home Theatre surround sound system?

[grim_tales]

Hey,
When I upgrade to 4K eventually, I'd imagine to take advantage of the newer sound formats (Atmos, DTS X etc) - I think I have to get a new system - was thinking of this sort of thing:

https://www.richersounds.com/yamaha-rxv6a-black/

https://www.richersounds.com/denon-avr-x2800h-black/

Can I still use my older speakers as Atmos speakers might be really expensive

Another option is s soundbar, but from what I read, the sound won't be as good as a home theatre though it does save a lot of a space. Is it a good enough option for watching movies?