Few care if you have a lifetime warranty and excellent service or replacement parts if the majority will upgrade in a few years! Mature technologies increasingly become cheaply available as services, eg. laundry, food, transportation. That further reduces demand on production, as many can get by with the bare minimum and don't need the highest quality, longest lasting appliances. Software is even more ephemeral and specialized.
Developing education and training pipelines is wasting money if the skills you need are constantly changing! There is plenty of "slack" in the workforce so this works just fine in most cases - somebody will learn what they need to get paid. There are very few fields where qualified worker shortages are a real problem.
R&D can be outsourced or bought and subsidized by the government in universities, so why do everything yourself? Open source software has even further muddied the waters. Applications have only a limited lifetime before being replicated and becoming free products (this has only been intensified by the introduction of AI), so companies develop services instead.
Technology and knowledge deepening and rapidly becoming more specialized makes the monolithic corporation much less practical, so companies also need to specialize in order to effectively compete. Going too far in the name of efficiency can destroy core competencies, but moving away from the old model was necessary and rational.