Well, supporting ARC is one thing your speakers don't. I just priced soundbars a week ago for my daughter's TV, as they had a couple of speakers die and can't afford a complete 5.1 system at this time. I got them a pretty decent 2.1 soundbar for $150, and that included a sub. It doesn't support ARC, and of course neither it nor your speakers also contain a Roku Ultra within it. So, figuring about $80 of the price is the Ultra, the another $70 for the soundbar is actually a pretty good price. It's adding the sub for an addition $180 is where it's past the bargain level. I'd say a total of about $200, and you get a Roku Ultra, the soundbar and the sub, that would be an exceptional deal.
The Onn. Roku Smart Soundbar soundbar connects to your TV via either HDMI or optical audio (S/PDIF). For more information, we'd recommend contacting Onn support.
You can also see more about the Onn soundbar on Walmart's website here: https://www.walmart.com/ip/Onn-Roku-Smart-Soundbar/642573197
(are there ANY TV speakers that aren't really **bleep**?) (rhetorical - TV Speakers are really **bleep** these days).
Yep, this is a physics problem with flat-screen TVs and what consumers demand from them. Because consumers want thinner and lighter TVs, they make the speakers smaller and smaller to fit in the limited cabinet space, and because consumers want a thin-to-non-existent bezel without visible speakers along the sides or bottom pointing at the viewer, the speakers on flat-screens typically point down or at the wall behind the TV.
If you want good sound, you need bigger speakers that point at the listener/viewer, and the market has revealed that people are more inclined to buy a thin/light TV with minimal bezeling and add external speakers or deal with the **bleep** sound than to buy a bulky TV with great speakers built into the face of it. The latter don't sell well, so manufacturers stopped making them.
ETA: I'm not sure why your post is able to say c r a p p y but when I tried quoting you it was replacing with "bleep" - just adding this note that I wasn't offended by your language and this forum is doing the censoring, not me.