I'm not trying to be an arsehole or anything but you seeking advice about jobs with minimal hours and lots of holidays (aka being lazy) is a very poor reflection of an individual seeking to enter this field.
There are many reasons why someone could want more reasonable hours. Perhaps someone has (or wants) children. Perhaps someone cares for elderly or disabled relatives. Perhaps someone is a serious artist or runs an animal rescue or is involved in church or is a competitive athlete. Or someone knows their own limits -- they have a chronic health condition that requires a certain amount of non-work time to maintain a safe and sane life. Or they just don't want to work more than full time and there is nothing wrong with that.
Being a vet is a privilege and it's a career, not a 9-5 job.
These things are not mutually exclusive. Calling something a career does not imply anything about the hours involved.
The reason this field is going downhill is because too many vets treat it as just another job, preferring to go on long vacations and work office hours.
There are many current challenges in this field including rising student loan debt, increasing technology and prices, changes in how pet owners obtain information and products, and veterinary mental health / suicide. I don't think this field is going downhill, but none of what most people consider the major challenges to this field have anything to do with people not working enough hours.
As a student seeking entry into this competitive field (which actually gets even more competitive once you graduate and are out in the real world!) the last thing you should be concerned about are cushy jobs. And every person in a cushy job has had to go through hell and back to get to where there at (residencies, phDs, etc are tough).
I am a practicing vet and there is nothing competitive about my life. I work with other vets every day and we help each other and teach each other new things. I am out in the real world as you say and it's not about competition - it's about the animals and about supporting each other.
Life ain't easy and it shouldn't be.
Life isn't easy. Being a vet isn't easy no matter how many hours you work or don't work. I hate to pull this card but there are certain things you cannot understand as a pre-vet student about what it's like to have the responsibility of a life in your hands, and to have a person's pet (and often their reason for living) with an open abdomen on your surgery table, and to give 100% to every patient and every client every day no matter how you feel that day because that's what they deserve. I am a good vet, I perform a service most vets wouldn't enjoy doing, I take care of underserved populations, my clients love me, and I practice good medicine, but I also know my own mental health limitations and if I was working more than 40-50 hours a week I would not only be severely anxious and depressed but I would NOT be a good vet. My life isn't easy. My life as a vet isn't easy, but I love it and I do everything I can to make sure I'm healthy enough to do this for the long haul -- including avoiding burn out and staying sane.
Veterinarians commit suicide more than almost any other profession. We NEED to support our colleagues and create a culture that promotes quality of life in and out of the work place. We NEED to give our colleagues the benefit of the doubt when they state their limits and boundaries. We NEED to stop tearing each other down and needlessly competing. Please do some research about compassion fatigue, veterinarian suicide, and burn out, and please consider changing your judgment of your future colleagues.
Also, it may interest you to know that James Herriot himself suffered severe depression and a nervous breakdown. I can't help but wonder if being on call 24/7 and severe overwork contributed.