Some enterprises can be coaxed into sales 'at the right price'....

Some enterprises can be coaxed into sales 'at the right price'. Others choose to remain 'family businesses'

When generations change, those who inherit may not have the skillset or desire to run such a business, even at arm's length. To be simplistic, they may just want the money..

Some Australian smaller rail operators operate elderly locomotives while their wagon fleet is also ageing. Nothing per se wrong with that, although older locos (like cars/trucks/planes) have higher operating costs and won't be as fuel efficient as modern examples. Failure rates may be higher, maintenance may gradually become harder if spare parts are challenging to obtain and each such loco may haul fewer tonnes than a 2021 newly built loco.

While they thankfully haven't necessarily succeeded AFAIK, bureaucrats are itching in at least one state to ban or further restrict higher emission older lcos, even though compared to road transport any emissions are negligible per tonne-kilometre.

LAU as a publicly listed entity has access to cheaper capital than most family entities.

I'll leave it to you to research smaller operators in Oz.