I had the same question about what rugged smartphones are out there. Here is a thread I started less than 3 months ago about the same topic. I still like the concept of the Ulephone Armor 7. In the end, I got a Samsung Galaxy 10 and then opted for the most rugged cases I could find.
https://www.rokslide.com/forums/threads/rugged-smartphone-for-outdoor-use.164797/
I ordered a number of cases and kept the two I thought worked best for me. For every day use, I chose the Otterbox Defender case as it was more protective than any other I could find. For outdoor use, I use the Juggernaut IMCT case and have mounted it on a folding PALS mount as depicted in the video at post #25 in the thread. It works very well for outdoor use and it is hands free if you mount the case.
If I were doing it again, and urgency of getting a smartphone was not a factor, I'd consider getting an iPhone as I found that there were companies that made rugged cases for them but not Androids. That said, I'm very pleased with my setup.
Good luck in your search.