I think it's too simplistic to say 'you make time if you love it'. Unless you have truly lived that person's life, you don't know how they are coping with whatever load is on them.
Yes, a lot of people make excuses and a bit more discipline is the answer - or at least a good thing to try - but not always.
A couple of years back I got a job as an editor of a trade magazine, while my son was still a baby. I found it so hard to do any creative writing. Sure you could look at my schedule and say 'why not write at lunch, why not get up early, why not write when your son naps on your days off,' but mentally I couldn't do it. I was writing all day, often taking work home, and always exhausted. I'm sure this sounds defensive but it's not meant to be, it's just how it was.
Saying all that, I did actually get one book finished and edited in that period, so obviously I was grabbing a bit of writing time occasionally, but I wouldn't say I felt happy or healthy and sometimes I'd go weeks without doing anything.
I changed roles a few months ago and I've read so so so much more since then, and got back into writing properly. I feel awake! I still don't have lots of 'free' time. I have a toddler now and not much evening to myself after dinner, but I have the energy to write at lunchtime, and I make the point of sitting at my computer most evenings whenever I'm not watching TV/relaxing with my husband. If I'm watching a show I don't particularly care about, I sit there with my work laptop (I can actually get a fair bit done this way - you have to do what works for you).
When I'm pure writing, rather than editing/revising I find it helps to have no internet, either in a coffee shop, or using a device like an Alphasmart - it just means I have no distractions. It's actually rare that I remember to do this, however.
