I said "companies of a certain size". Don't make this into a socialism vs capitalism issue. Yes, companies benefit society. But I believe trillion dollar companies are a negative for society. They get way too powerful.
Only if they use their power to more bad things than good things.
Same with governments and the attempts at state capitalism you're referring to. Everything always is good unless it's bad, the question is how easily can it be constrained when it goes bad (and monitored for the signs of it going bad).
Which they do all the time with no consequence.
By the same line of thinking dictatorships are also only bad if they use their power for more bad things than good things.