You may have forgotten it because it’s not something that many people use, but most modern iPhones are ready to work with two SIM cards (they even use 5G since iOS 14.5). This allows you to manage two phone numbers (such as one personal and one work) on a single phone. And now that management will be easier with iOS 16.
Two SIMs, two message lists
From that version it will be when the Messages app will separate those arriving from the first SIM from those arriving from the second. The feature has appeared in the second beta of iOS 16 recently released to the developer community.
We will see the option to filter those messages by SIM precisely in the filtering options that we can activate in Messages to also differentiate messages from strangers. Yes, we will have to have those filtering options activated to be able to use this novelty.
iPhones that support this feature are iPhone XS and all subsequent generations, counting the slot for the physical SIM and an internal eSIM. The iPhone 13s are also capable of using two eSIMs, being able to completely dispense with internal SIM cards.