A margin call is not the same as a foreclosure. It’s quite different. You have a fixed payment with a mortgage. If the value of your house declined precipitously, that fixed payment stays the same. You enter foreclosure proceedings only if you cannot make that payment, and depending on the state, this takes some time. You might be living in your house for a year or more without making a payment while in foreclosure.

On the other hand, with a leveraged position in the market, if the value of your portfolio falls to a certain level, you either need to post more capital or your position is liquidated. If you are capital constrained, there is literally nothing you can do in the case of a leveraged position - your broker forces you out.

Regardless, if you keep making your payments, there is no way for a bank to force you out of your mortgage or call for additional capital due to a decline in value. This is the big difference.