Well, guess what. It did in fact do that in certain places. And then it self corrected...
Hasn't worked well for healthcare - UK consensus among healthcare experts is that there is little/no role of private companies in healthcare provision. Growing consensus also for train transport given lack of competition that can realistically occur on 1 line.
UK consensus? Don't make me laugh. You mean a bunch of "healthcare experts," employed by the government, say what they are told to say - if they want to keep their jobs.
I mean, do better than that. Please.
Growing consensus for train transport? I don't even know what that means. There's no "growing consensus" about the wisdom and economics of Amtrak. There's certainly no "growing consensus" about the wonderful utopia of Argentina's trains.
But hey, nobody ever said that every single last aspect of a society should be capitalist. And some aspects change with technology. As an example, it was once clear that most roads might best be done by the government for the general good - but that was the era of paper money.
I personally don't think that's true anymore with efficient micropayments and scanners possible. So these things can and should change with time and with technology. One argument against "government services" is that they are much less likely to change with technology, and much less likely to remain, or become, efficient and cost effective.
Have to be very, very careful when trying to make big, sweeping generalizations.
Healthcare professionals and scientists are interested in improving health, not being biased towards government. See BMA and other groups output, usually in response to government imposed changes. Compare and contrast the UK's expensive and price discriminatory private train lines with other more efficient publicly run ones (eg France). Majority of the UK population support rail re nationalisation