I have ALWAYS had to sign for the iPhones I bought from the Apple Store online.
Both FedEx and UPS require signatures if the sender requests that they get one. Apple usually sends computers and iPhones requiring signatures. YMMV.
I think it depends both on what the vendor says and what the UPS/USPS/Fedex/Amazon delivery guy policy is…and the policy varies depending on area, whether COVID was happening, the individual driver, the phase of the moon, and who knows what else. We’ve had signature required items just dropped off (we live in a gated community that’s a pretty safe neighborhood so maybe that has something to do with it)…and we’ve had to sign for little stuff like watch batteries.
Neil makes a good point that there are many variables we may not know. Early Sunday morning I was out in the front yard when I saw a woman walk along the sidewalk then turn into our walk. She was wearing an Amazon shirt and when she saw me she and handed me a package. I didn’t remember ordering anything, and when I glanced down I saw the package said LITHIUM BATTERIES. She had started to leave (without asking for a signature or talking a photo), and I stopped her so I could read the address. It was for the next door neighbors, so I handed it to her and watched her deliver it.
A few years back we received an email from Amazon saying they had delivered a package to our doorstep and got my signature. We didn’t sign for it, and it wasn’t on the doorstep – a porch pirate had opened the box and dumped it in a snowbank, disappointed by the contents. That’s not the only time Amazon wrongly claimed they had a delivery signature, but it was the only attempted theft.
Depending on the number/value of packages one receives, it can make sense to rent a mailbox. Some post offices offer signature services, and most commercial mailbox services (like the UPS Store) are able to sign for packages on your behalf by default.
Rates can vary widely depending on location. I spend around $250/year on a UPS mailbox in New England. That sounds like a lot, but it’s very convenient for me, and I find it to be much more reliable than any delivery service to my home address. I now use it as my main postal address, and I’ve received several Apple devices there via courier without any problems.