I'm probably taking you too literally, but if you really get all your local stations on a 1980s TV, then the trouble is that your local stations are still transmitting in NTSC and modern sets aren't designed for that!
That said, I do think that many of the manufactures of "Roku TVs" are in the third tier/fourth tier/fly-by-night range. Sometimes you'll get one that is fine, but I'd rather have a Samsung and just plug a Roku into it. Last time I checked, Samsung had the highest reliability rating in Consumer Reports. However, it's been a while since I've needed to check (because I picked a reliable TV, I suppose) so things may have changed.
Keep in mind, that Roku doesn't manufacture any TVs. That might actually be a good thing for you though, since you're complaining about a lack of Roku support – ie: for a TV, you go to the TV manufacturer for support – not Roku. So, maybe the TV manufacturer actually has some!?