No offense, but being in my mid-20's I'm probably relatively young compared to y'all... so if there's going to be a time that I ride sport style bikes, it's going to be now while I'm young rather than later. As age wears on my body, I'd concur that I'll probably shift my preferences towards the more physically comfortable cruiser and touring style bikes. However, for a bike that I plan to only own for a year or so as a means of leveling up my riding skills and then resell, physical comfort is not that big of a deal for me. If I learn to ride a sport bike safely and proficiently first, adjusting to a cruiser later isn't going to be difficult at all compared to the other way around in my opinion.
Remember the bike I'm getting is not a supersport, it is definitely designed for noobs like myself since the seat isn't level or raised higher than the handlebars like other sports bikes and designed to be more comfortable to noob riders.
When the time comes that I want to upgrade to a 600cc+ bike and a bike I will want to ride for longer distances at a time, comfort will be more of a factor. But since I don't plan on riding this bike for extended distances and only for joy rides and the short commutes to work with the sole intent of gaining riding experience and familiarity with sport style bikes, I think I'll be able to cope with any physical riding discomfort that I may discover, if any.
I sit at a computer for most of the day, so in terms of my posture... it's horrible... I don't think being hunched over on a sports bike is going to be much of a change but an improvement to how I sit in my office or while driving my car. But hell, what do I know.
Also, while I know this is a superficial reason, one of the factors that has influenced my decision to go with a sport bike over a cruiser style bike is that sports bikes have more of a "cool" factor to me, and they appeal more to an image that I can see myself fitting easier. I just can't see myself, a relatively skinny, young, Korean guy at 5'7" 140lb riding a Harley.
Superficial, sure, but I'm stubborn and insist on a sport bike as my first ride... I admit it may not be the wisest decision, but again I'm young and wisdom concerning this falls within an acceptable amount of risk and is something I can afford to lack in this situation. However, stubborn or not, I do learn from my mistakes and I'm serious about safely learning to ride, so if I'm going to hate riding sport bikes, the best thing for me to do is find it out on my own and change my personal preferences accordingly.
Nonetheless, I hear what y'all are saying and understand where y'all are coming from... I value all the opinions that have been voice, independent of whether I agree or disagree with them.