Reading about how your hearing goes in an open top vehicle reminds me that I suspect in retrospect that that’s how I lost some of my hearing. Our daughters as teenagers got relatively newer cars to drive with AC, I drove older family cars in which the AC had broken and we were too cheap to repair with a new compressor, etc. I was driving as high as 75 mph with all the windows open and the radio blaring loud enough to be heard over wind noise so I was probably at least in the 90 to 100 dB sound range due to the radio adding quite a few dB. Hearing loss is a well-known side effect of motorcycle riding, too, and a large part of that is the wind noise, not entirely the sound of the exhaust. So probably pleasure driving at city and neighborhood speeds is OK in an open top vehicle but I’d look out for many hours (4 or 5) at a crack, 8 to 10 in a weekend round trip as I was wont to do in middle age. Hearing Loss Caused by Driving With Windows Down, Radio Turned Up Loud? - #2 by jim_lewis
I think just as people, especially young people, are not very accepting if you tell them that extremely loud music at rock concerts is not conducive to maintaining good hearing, most people probably don’t want to believe freeway driving in a convertible could hurt one’s hearing in any way.