Blackrock doesnt have any 30 year debt (they have a very debt-light business model). Microsoft has 30 year bonds and theyre trading at around 4.5% right now. But of course, the default rate on AAA corporate debt is much lower than on Joe Schmo's mortgage.
There is 900 million farm acres of farmland in the US. Bill gates owns about 270K acres of farmland. So even though he is the largest private owner of farmland, he owns less than 0.1% of all farmland in the US.
Ref: https://apnews.com/article/fact-check-bill-gates-blackrock-7...
That doesn't mean half the homes are now owned by these corps, just half the homes purchased in last year or two were by corps. But in some cases they've bought whole subdivisions in one shot, so it's not too far from reality depending on the area.