Years ago when Manchester ran its own buses, it certainly trained its own drivers. There was no cost to the individual, though I don't know if there was any contract requiring you to stay with them for a given period. However, let us look at the modern world:
Is bus driving a job that gives you status? No.
Does it give you high pay? No.
Is there a load of hassle with the job? A fair amount.
Is its secure? Reasonably, but not a job for life.
Are there good terms and conditions? No. (There used to be back in the days of the 'inefficient' public sector.)
Is there an index-linked pension when you retire? Don't make me laugh!
Is the job an important role in society? Yes, very much so.
This set of questions and answers applies to many jobs in the current world. The fact is we have allowed a whole load of important jobs to become unattractive, and on top of that, we often expect people to qualify for them at their own expense.
We now have a serious shortage of labour despite the fact the economy is very far from booming.
We need to be realistic. a) We need more immigrants, certainly in the short term, whether people like it or not. And b) (equally important) we need to stop treating workers like disposable shite and accept that although they may be relatively low-paid their role in society is vital, and needs to be better recognised and rewarded.