Ultra Wide all the way.
Harder to mimic ultra wide result with standard wide focal length (possible via manual photo stitching or using panorama mode), but easier to achieve telephoto focal length result.
Here’s example steps how:
1. Normal result with standard wide focal length:
2. Crop it around this much:
3. Adjust the bokeh effect realistically according the distance between each objects:
4. Final result in comparison with telephoto focal length:
You can always crop in post processing to achieve telephoto result (never digitally zoom, degrades quality).
But often you cannot step back for wider framing of family group shot indoor or landscape photography.
Most professional / enthusiast amateur photographers would pick a wide lens over telephoto lens if they can only bring one lens with interchangeable lens camera body. Especially with higher megapixel counts, more room to crop in post.
Too bad iPhone kept the 12 MP sensor only.