In short yes. You will lose all benefits of Atmos.
But also. What are your expectations of Atmos performance from a soundbar? Set up correctly takes at least five speakers at ear height, plus a minimum of two on/in ceiling or at least in a “height” location high on the front wall, or side walls. Imo, Atmos from a soundbar is dubious at best. And from what I understand eARC can only pass Atmos in a lossy form.
For the money you’ll spend on a decent soundbar, you could easily invest in a nice 2.1 system, or a budging surround system. Keep I mind too that the “subwoofers” that come with soundbars are not good.
If you really need a more minimalist look, it seems yamaha makes a “decent” soundbar.
You should know, not many here are fans of the soundbar, so you might not get much traction, but there definitely are some.
Good luck.