YANBU to want what's best for them, whether that turns out to be university and a "professional" job, or straight into a job after school, or something else like a gap year, a degree and a non "professional" job, or doing a degree on the job.
However, be careful that their choices are theirs, and that they don't feel you're trying to put them off university and a professional job, any more than pushing them towards those things. You didn't like uni but many people do and it can depend so much on the place, course, people etc.
I was lucky enough to enjoy university in many ways. You get to meet so many different people with various interests to broaden your horizons, you spend time on a subject that fascinates you, and develop many transferable skills such as research/analysis/presentation. It's not about making money but about developing your mind and as a person. And after a degree you've still got the rest of your life in the world of work.
Some of my school friends opted for going straight into work after university and were happy with their choice. One or two seemed to find it necessary to make comments that university is "a waste of time" instead of recognising different things are right for different people.
I haven't ended up in a high-flying professional career but I don't regret university for one minute. I see university as an all-round experience, and beneficial in its own right, rather than learning a set of skills for one job.
I think these days many people aren't that bothered about the "prestige" of where someone works. Some people make judgements (one of their first questions will be "What do you do?" and you can sense the calculation going on after you answer!) and I have felt judged sometimes. But most people are interested in the person, rather than how they earn a living.
If your DCs have all the information in front of them, maybe some university prospectuses/visits and some time researching jobs you can do straight from school, and perhaps some work experience, they can choose what they feel is best for them. Then it's their choice, not someone else's ambitions or expectations.