Not the same at all. Years ago I thought the same, so I bought a Mustang GT convertible. Didn't realize what a hurricane of wind hits you in a convertible at freeway speeds - something you don't have on a motorcycle, especially when protected by leathers and a helmet. There is a suction around the front seats caused by the windshield; depending on how fast you are going, if you have a lady along her hair is either swirling around or pulled forward toward the windshield. My wife hated it. Only time it was fun was in a place like Yosemite where speeds were slow and with the top down you could see the towering cliffs, which you can't see from inside a sedan.
Plus...when you park in public places an open convertible seems to be an invitation to vandalism. I'd come back to the Mustang from a quick trip into a store and find all kinds of garbage had been thrown into the car. So I had to put the top up and close the windows if I parked in a public place. Sold the car after 5 years.