Why hasn't Roku come out with a device that you can hard wire to your internet. I have 5 tv's and 5 Roku's. I have periodic issues with connection which means every day. If I could hard wire the device it would eliminate the problem.
The Ultra has an ethernet port, most of the TVs do also. Of my 5 TCL TVs only 1 (cheapest 32") doesn't have ethernet.
That said, 3 of those 5 TVs and a stick in my garage are all on Wifi and I haven't had any issues. Wifi is extremely reliant on environment and equipment.
We use the Ultra because I did hard wire our TVs with Cat 5 cable. I did this partly for performance of the TVs themselves, but also just to keep that bandwidth off our WiFi. (With video doorbells, laptops, tablets, etc. etc. I figured just why clog things up for the pretty much stationary 'it will never move' stuff.)
It would be nice if the smaller sticks had a port or if they had a less expensive hardwire option. (The Ultra was more expensive.) But the way I look at it, it's a one time hit vs. what it used to cost to rent the cable box.