You need multiple lines of defense. Insurance is number 1. LLC is number 2. Not creating an LLC because you're unlikely to get sued is the same as not getting hazard insurance because you're unlikely to have a fire. Bad idea.
But regarding creating a single LLC for each property, that is fine for 5 properties, but with 50 or 100 that would be a nightmare if you have separate bank accounts and books for each one. And the legal fees and accounting fees could be quite onerous.
There is another option where you only need 2 LLCs. It is referred to as equity stripping. You have one LLC that owns the properties, and a second LLC that loans money on each property. Even though you are the owner of both LLCs, these are still legitimately separate entities and legitimate loans. The loans should be for the full amount of the property value or higher. If you have a bank loan on a property, you can set up a second loan from your lender LLC, to cover the equity above the amount of the bank loan. You can set up the loans so that the interest accrues, so you don't have to track payments.
Your lender LLC is unlikely to get sued, since it has no "risky" activity. Your property holding LLC is unlikely to get sued, because it has no equity. But if your property holding LLC does get sued, the creditor would have a tough time getting anything out of the LLC. In the case of a judgment, your lender LLC could even foreclose on the property and take the property from the property holding LLC, thereby wiping out the judgment.