This is generally true. However, some cities have unbelievably bad streets riddled with potholes. IMO, wide knobby tires do better over unkempt partially paved streets. Most hybrid frames can more easily accept these types of tires. Cities like Detroit, New York, Chicago, and Cleveland are hybrid commuting cities!
Do any of these cities do the infamous gravel "patch" that Saskatoon does? I never saw this strange idea of road repair before moving to Saskatchewan. The idea is, they dig up the pavement around a pothole/s, toss a pile of gravel down, then many weeks or months later, come back and actually pave it. I think the idea is to use people's personal vehicles as tamping machines. A bike is often the best way to travel on roads that have a lot of these, because you can carefully skirt the edges.
I'd say hybrids, mountain bikes, and cyclocross bikes are most popular here. I see more 'cross bikes than road bikes used for everyday travel.
For me, I found my ideal commuter a short time ago. I used to ride my hardtail MTB with slick tires but invested in an old Mercier road bike I found in a 'vide grenier' (fleamarket) a few weeks ago. I paid EUR 50 for it and it beats my fancy MTB for my 6+ Km commute. It has holes for fenders and racks but luckily, I work for a company that has bike parks and shower rooms, so I only carry a change of clothes in a small backpack and shower before going to my desk.
I have probably spent over EUR 100 on it, but still it's a very inexpensive option. I intend to keep upgrading it, but want to keep it especially because it's not a 'desireable' bike, so I feel comfortable riding it around town.
Mongoose Ledge 2.1 (heavily converted into a commuter bike)
Adding to what everyone in this awesome thread is saying, I'll say this.
Will any bike do? You're flingin flangin right it will. Wheels and pedals, all you need. (Handlebars help too, but lets not split hairs)
Based on my experience, I would say once you get that bike, go ahead and make modifications and what not to suit what YOU like. I had a trail bike I was using to get here and there. It was awesome, but then I started looking into purpose built commuter bikes. They all were pretty much same concept as my bike, but no shocks, and single speed. I don't want single speed. Other people might, but I'm not those people. So I thought, why don't I just make Mindy into what I want. So between this and training for my century, and with some help from the owner and really hot girl at the LBS, I customized my trail bike into a commuter bike.
I didn't like trail tires, so we put on road slick high pressure tires, made for just such a thing. I like taking my bike some places it wasn't intended to go, so I like having the spring in the middle and I really like the frame and its shape more so than the commuter bikes, so we left that, but adjusted the tension for not riding on trails. The factory saddle was made for fun rides and not being in it for hours on end. Swapped that out for a more comfy saddle purpose built. My shifters weren't intended to shift back and forth so rapidly... off they went, and more heavy duty shifters went on (I like grip shifters, back off). So those things, and a lot of subtle adjustments to crucial points... boom. I had a commuter bike customized to MY needs.
Long story short, yes... use whatever bike you want, but know that you don't have to, and probably shouldn't, ride it how it came off the proverbial assembly line. Make your bike your own. You'll be together for a lot of hours a day, make it comfy.