@Andy,
Yeah, could argue those 'positives' of state-directed/state-controlled. Point was manipulations to economic and societal invisible hand, causes unintended results.
Logical decision, for those with power, isn't really being prevented in any of those cases. One carrier, one route is residual of decentralization during one of the more free-market periods, assigning broken up pieces to the administrative regions, then trying to partially reverse it later. Guessing heads of each of those SOE airlines weren't keen to give up power.
-Extensive rail system when you "acquire" the IP from someone else, saving the R&D of internally developing it, then award contracts to the SOE saving all that IRR and profitability type nonsense. Not illogical to favor the firm domestic firm over the foreign firm in the IP dispute. Kickbacks were working out great for the Railroad Minister until he was signaled out as the fall guy after the cover-up of the collision didn't work out.
-Not illogical to attempt to prop up domestic firms over competing with foreign firms via lower worker cost, lack of environmental consideration, and currency-devaluation. Worked until others imposed import tariffs to counterbalance the artificial lower costs of the exports to undercut competition. Beijing becoming almost naturally uninhabitable has certainly put a damper on it as well.
-New infrastructure is often easier to begin with, then add less worker rights, disregard of property rights. Ghost cities, officials-endorsed contractors running off with investor money, officials being chased out of town after trying to convince farmers to sell their land for pennies on the dollar in exchange for a kickbacks. Construction companies debt levels on their balance mean they cannot be allowed to fail.
Sounds sustainable with the massive monetary and intellectual capital flight accelerated by depreciating Yuan. At the moment a good chunk, when they can, are choosing to leave that brilliant low-end commodity producing, new infrastructure company. Voting with their feet and their wallets.
More-efficient than back-door lobbying, pork-barrel, vote bartering, pro quid quo of Western systems? Yes. Sometimes sound better than trying to build a new airport or rail-link without having to get approval from every Tom, Dick, and Harry at each level of government, and build it without having to guarantee X% of contracts sourced to union-labor and at market cost of capital? Sure. But doesn't sound so good if you have minimal workers rights, reduced freedom of movement, company success as much about connections as operation, etc.