After a couple of back surgeries I was talked into a bent, having not ridden a bike for about 50 years.
Much to my surprise I found I grew to love it, - no back pain, no butt pain, no carpal tunnel or sore shoulders or stiff neck from an upright, which I tried a bit. Also, much fresher at the end of a day or a century. No comparison. I tell my wife I don't need diapers and boxing gloves like whe does! LOL
I truly believe that a lot of upright bike riders would ride bents if they actually got over the 'wierd looking nerdy' aspect of them, and gave therm an honest try. They do tend to be a bit more expensive than the average upright, lwhich might put off a few would be bent riders.
But in terms of comfort, there is simply no comparison. A bit faster on the flats and downhills, a bit slower on hills, so speed is a wash in my opinion.