I think "onn" is just Walmart's "store brand" for generic electronics[1]. Kind of like "Insignia" and BestBuy. The design and manufacturing is all outsourced and these are usually quite crappy as one would expect.
> Walmart is Onn’s parent company. Onn is Walmart’s generic brand electronics label, and Onn products, including Onn TVs, are only available in Walmart stores.
[1] https://sycamorenet.com/blog/who-makes-onn-tv/
