If someone points a gun to your family are you not going to open the safe?
A multi sig such as a 2 of 4 or 3 of 5 poses a greater challenge for an attacker to overcome as he now has to drive you to a second or third location to get the other keys, and it gives the user margin of error as he can afford to lose access to 2 keys and still be able to recover the funds. With a single key, while it works just fine in a lot of cases one most likely will either keep the seed and/or signing device at home where it is easy for an attacker to coerce you into giving up your key, or at a safety deposit box or similar location where a third party might be coerced by the state to give them access to your stuff (seed).
Granted not everyone is at risk of a physical attack depending on where you live and your lifestyle.
But when you have a large portion of your net worth in bitcoin I would think twice before having a single point of failure. That is why I said I hope everyone doing that carries a gun and is able to fight back against a physical attacker.
It was true in the past that a multisig was not user friendly for beginners, and many ppl lost coins because they fucked up something. That problem has been solved with collaborative multisig products like those offered by Casa, Unchained, Nunchuk, and others.
If you’re not already doing this I recommend you SEED XOR your key and implement a login countdown of at least 24hrs on your signing device if it happens to be a coldcard.