Unions and pensions and oversight are good things that help ensure people are treated fairly (or at least, better than they otherwise would be). I want my tax dollars spent giving locals a decent retirement, and not going into some California VC's portfolio.
And "no easy allocation of resources" strikes me as a good thing as well. This is public infrastructure. People depend on this for their daily lives. The last thing we want is for it to be easily unallocated.
So for example, if the demographics of the community change such that transportation needs change, or technology changes (automation of many kinds) meaning fewer employees needed or different kinds of employees are needed, it becomes hard to reflect those needs in the workforce because of the union agreements.
No, its just that -- with the 1980s and beyond push for privatizing governments services -- we now have experience as well as pro-corporate astract theory. And while experience has sometimes shown some benefits, its shown a lot of problems with privatization, as well. (Including that it often promotes a particularly intense, single-beneficiary variation on regulatory capture.)