Jail breaking has nothing to do with radio reception. It seems you neglected to mention coverage in remote areas which is really the issue. Everyone has good enough reception in major metropolitan areas.
I’ll stick with my comment which is really important. You need to support as many channels as possible. It doesn’t do you a bit of good to have good reception on channel x if x channel isn’t available. On the other hand, if the antenna supports y, and you have a radio that supports y, you are good to go.
Bottom line, newer better radios support more channels and when new antennas/towers are added you have more likelihood to have reception.
To make it easy, here’s a link of a search.
https://www.google.com/search?q=smartphones+with+best+antenna&rlz=1C9BKJA_enUS771US771&oq=smartphones+with+best+antenna&aqs=chrome..69i57j69i60.8576j0j4&hl=en-US&sourceid=chrome-mobile&ie=UTF-8Fwiw, I don’t hate iphones. My wife likes them. I’m using an iPad Pro at the moment. There was a time when her iphone was better, but now she has an iPhone 11 Plus and it has no signal where my Note 10 does over the pass along I90 for instance.. Take it for what it’s worth. But from what I’ve seen as well, there’s defintely a diffference in the phone you have. Of course, if you are locked into Apple Ecosystem feel free to buy one.