401k loan instead of mortgage??

[Christian Weber]

So I was watching YouTube and a "guru" mentioned you can take a loan out on your indexes/stocks as it is a secured loan at a fraction of what you would get on a regular loan (1.5% instead of the 3-4% on a regular conventional loan) and that you can borrow around 40-60% of your portfolio amount.

I looked online for info even close to this but couldn't find it, I have a sizeable 401k so wanted to look into this - any insight greatly appreciated