Your kids are very lucky that they have parents who have the ability and are willing to back them up.
There are many that aren't in that position.
Society shouldn't be functioning in such a way where parents have to fund their children's housing.
We are creating an underclass where people can't even afford rent. E.g. the homeless over 50 women sector that is growing rapidly.
All these baby boomers that bought their houses 40 years ago never dreamed that they would be worth so much money today. They just wanted to own their own house for a bit of personal security. They didn't want to profit from it and exclude others.