I understand your concerns and this seems to be a bit more of a larger concern with the online boot camp path as a whole. Coming from Career Foundry as a student still and not even half way done with the course I could answer a lot of this since I did my own research prior to joining any boot camp at all. Yes, its a large endeavor that requires some money and a lot of time along with hard work. All the courses are made so you do and get real life hands on experience that employers look for along with a strong portfolio. I can't speak directly for UX Academy but at CF the final goal is to have done the processes that a real UX designer would have done during a project. We build our portfolios with this content and get real-time feedback from people already in the field along with career coaching etc. So to be blunt it's worth it as long as your willing to put the time and effort into the course yourself.
I suggest hopping onto Linkedin if you have a profile or create one and look at people who have these courses as part of their education and see what they are doing now. I find a lot of my peers and alumni have finished the course and graduated and are working in the field.
If you have any questions in relations to CareerFoundry and their courses etc let me know. I can speak directly for them. And of course, any other unrelated questions please also let me know, helping someone new to the field is something we all do here!