Personally I believe each of these can have advantages in various situations. Some critical shared infrastructure and services I think do belong with government. Defence, healthcare, emergency services, perhaps some utilities. Charitable trusts have a place. But I also believe private citizens that demonstrate the ability to build and run businesses also have a place, a big place in the system. Private capital investment is a massive and highly productive and efficient force for economic good. Typical billionaires don’t spend billions on themselves. Millions yes, but most of those billions exist as shares that represent control of productive businesses that provide goods, services and jobs. If they spent it all on themselves they wouldn’t be billionaires for very long.
I don’t think it’s generally in the public interest or beneficial to society to confiscate businesses from their owners, and what? Give it to who? There is a legitimate concern that such control can lead to negative effects like exercise consumption or political influence, but the way you deal with that is to address those problems directly.
Did you mean 'excessive'? Or is this a term I'm not finding on Google?
That depends on the degree of centralization of any given variety of socialism. The other option is that they are owned and managed directly by the workers.
The main reason I think we don’t see cooperative worker owned enterprises very often is that employees generally are not interested in assuming the level of financial commitment, responsibility and risk that goes with ownership.
Sure, they didn't do it alone, they had employees and the whole rest of society, but all those workers and the rest of society was there before and yet the business was not. Successful business enterprises don't just instantaneously spontaneously assemble because the world is capable of supporting them, they have to be created and if they cease to exist the world is worse off even though all the workers and buildings and so on still exist. (Also, the parts of society that enable successful businesses - and even basics like food and energy - are much more heavily made up of other businesses than I think people appreciate.)