In South Africa, there is a huge difference in shifting from Sole Prop to Company, financially it is not viable and it's a huge admin nightmare. Using your personal name is unprofessional, it doesn't help any bit in launching a business. Apple really needs to reconsider this decision. Apple needs to allow the use of a fictitious name. Why is this such a problem?
I understand it is a problem as Apple wants to keep the Appstore as trustable as possible for users. So buyers need to know who they are dealing with: either a physical person or a registered corporation. But not a physical person mimicking a corporation.
But you can file a bug report with a suggestion.
Yes, the situation in the UK is as you describe: a "sole trader" is relatively simple administratively (i.e. just one additional section in your personal tax return) but Apple will only show your personal name in the app store. Actually forming a limited company here is not too difficult, but subsequently the tax admin is quite considerable; you have to file accounts for corporation tax, and you have to manage both the employer's and the employee's side of paying yourself a salary. But you get to put your business name on the app store! Of course you do have the option of employing an accountant to do all the extra stuff for you.
I did this change about 4 years ago. Now that I know what I'm doing, I'd say that it takes a couple of days per year for the corporation tax accounting and a few hours per month for the salary payment accounting. So maybe it has reduced the time I can spend on useful work by 4%?
If I understand correctly - which I may not - in the USA they have the concept of "disregarded entities" for tax. So if you establish an LLC with one owner and one employee, that is a "disregarded entity" and you are taxed as if it didn't exist. That makes things simpler. Am I right about that?