iPhone connects to XM hotspots that don't deliver data; does everybody have this issue?

I've got an iPhone 6 on iOS 12 (the final supported iOS version). It automatically connects to XM hotspots, but often the signal is too weak and I get no data, so my streaming audio stops. I tried to stop it from connecting to hotspots at all, but failed (I can tell it to forget a particular hotspot, but it will still connect next time I'm in the area and will also connect to all other hotspots). So if I can't do that, can I at least get it to only connect to hotspots with a strong wifi signal? Does it work that way for people with newer phones?