@Dale1098 I can see that your complaint is mainly towards Major Property Management and yes they might be not as lenient as most of the small hosts on Airbnb, but that is no reason to shout (capital letters) or rant at people who are agreeing or disagreeing with you.
When you book a stay through Airbnb, you are notified about the cancellation policy. Each individual listing is different and hosts can choose what policy they would like. It is up to you, the guest to read these details. When you make the booking you are agreeing to these terms. If you haven't read the details in full, that is not the hosts fault.
Saying that some hosts would offer off their own accord to give a refund if your cancelled dates are re-booked, but they don't have to legally do that, it would just be a moral decision.
Unfortunately if you book with a big major company, that is the risk you take. For them it is just business !
I like many others offer a refund if rebooked but like @Kia272 & @Mike-And-Jane0 said it is down to you the guest to the read the details fully before you book.