Towing speed for small pop up ?

I don't tow anything much above 65 mph. Any trailer tires I've seen have 65 mph max stamped into the sidewalls. I have towed a small vintage tent trailer with 8" wheels at 65 mph with no problems. The tires are new and the bearings were serviced recently. I felt the hubs at every stop and they were only warm.
A big bump in the road, a pothole, or any kind of unanticipated reason to swerve or brake hard would be a lot easier to handle at lower speeds.