Things are both simpler and more complicated in the UK. Simpler because the rules are quite clear (and very fair) and more complex because company managers tend to make up extreme rules that are way beyond what is necessary. Job application disputes are not settled in a standard court, they go to an employment tribunal instead and are decided by one judge and two independent lay-member volunteers (often councillors,…
To be fair, it was quite clear that I didn't want to work at some of those companies and if I'd have been asked to give them feedback I'd have phrased my disinterest in similarly brief and diplomatic terms which wouldn't have told them much they didn't already know or weren't inclined to disagree strongly with.
Even if the tribunals are inclined to side with the companies, companies' fears are still well placed. A perfectly reasonable "unfortunately we didn't think you had the appropriate experience for the job" can become possible evidence that they were concealing discrimination should the company subesquently hire someone similarly lacking in experience but in every other way perfectly suited to the role. Companies seldom announce their decisions to reject a candidate are based on racism, sexism, homophobia etc even when they are.