Unlocked and SIM-Free mean

Unlocked means no specific ties a cellular carrier, usually because you paid full price, and received no carrier subsidies. Carrier locking is an electronic lien. You can’t use a carrier-locked phone with any other carriers.

SIM-free and eSIM mean no physical carrier SIM is required. The internal eSIM is populated and maintained and can be changed electronically. The SIM being a small chip used to authorize your phone on a carrier network; your telephone number, billing, a d related are tied to the SIM. Or to the eSIM.

Swapping SIMs on an unlocked phone means you can easily switch among available cellular carriers. “Swapping” an eSIM yet easier.

If you received a subsidy when you purchased this device and have subsequently completed your carrier contract, various celular vendors can be willing to unlock the phone. Check with your carrier for details.

Unlocked means it can work with a sim card from any carrier. Since you changed from Verizon to xfinity, that points to it being unlocked. If it had been locked, it would only have worked with Verizon, and using a sim card from Xfinity would have issued an error.

Sim Free, means it has no sim inside. i.e you have removed the sim.

However, generally those questions are not asked when trading an iPhone in, they are asked when buying a new phone.

When selecting the new phone, you decide whether you want to get it through a carrier, or unlocked so it can be used with any carrier and it would have no sim card inside. You would have have to provde one yourself.

Ah, so you have somewhat different questions.

Whether the iPhone is now carrier-unlocked (it is)...

and whether it was originally purchased carrier-unlocked (donno)...