I agree that if you’re new to the IT profession or changing careers then the initial re-skilling and education can be pricey, but that would apply to most professions in this scenario. Although employers are unlikely to provide you with equipment, most medium to large IT employers would send you on a course every 1-2 years at a minimum, else you’re probably doing something wrong.
Once you start getting into “real” contracting (ie. Multiple simultaneous clients), I don’t see the appeal of an Umbrella over a Limited company. Sure, in the Limited case the money is still coming out of your gross earnings, but let’s be honest, how many IT technicians wouldn’t buy the same toys to play with anyway? I’m on the software side so the “necessary” outgoings are arguably less but my hardware (network and AD) friends love to tinker with VM’s and what not. Usually it’s on older hardware which would’ve been replaced anyway.
The people who are serious about keeping on top of their profession should be making enough that £5k+ a year on hardware and training should barely phase them. Most IT professionals I’ve worked with don’t spend beyond some books from Amazon and free information on the Internet. Although they may not be making a six figure salary, they’re happily employed. I just don’t feel that the cost of entry or up-skilling in IT is as high as you have suggested. Sure, you CAN spend a lot but it’s arguably not necessary.