I think it's largely depending on the person which of those sounds more tiring. An extrovert would thrive on these meetings, while an introvert might hate every second of them. Conversely, an extrovert might hate sitting alone in front of his PC for 60h, while an introvert might find it very fulfilling (assuming that he loves writing compilers).
No they don't. They do it for a brief period when they are interns, under the theory that if you only have 2 years to make someone a good enough doctor you need that many hours per week to accomplish it.
The majority of doctors work 41 to 60 hours per week. This is self reported, so it is likely that it is somewhat inflated. I once met someone who claimed to work 180 hours one week (do the math).
Yeah, it depends on the work and the person. I've had periods at my company where 60h absolutely would have been sustainable for what I was working on at the time, and periods at the same company where 40h is still headed towards burnout. And I've experienced much worse elsewhere. I actually really like the periods where I have stable things that give back enough energy to keep me sustainable at 60h.