The Garmin watches will display incoming phone calls (and allow you to silence them and send to voicemail) and text messages, and some of the latest Garmins will (like the AW) allow standardized responses ("on my way," "call you later," stuff like that, I believe). I think the latest Garmins (some or all of the Fenix 8 series) will also allow voice control of things like timers and stopwatches, which is useful when, e.g., grilling steaks and such.

The key is that the AW is a great smartwatch with some fitness features, though it doesn't add any features beyond your iPhone's capabilities -- it just puts them in a wrist-sized package. Garmin, on the other hand, makes a great fitness watch with some smartwatch features added in -- though the latest Fenix 8 models are really quite "smart."

It can be a bit bewildering to compare and evaluate them....Might be good to start here and look at the Product Reviews section. My other piece of advice is, if in doubt with the Garmins, just spend more money, as that will always get you more ruggedness and more features.