I'll preface this by saying there's nothing I like better than an outstanding wide landscape where the viewer can w"walk into" the photo.
On my latest trip to Iceland, fully 30% of my "keepers" were made with a focal length of 35mm or less, with ⅓ of those (10% of keepers) at 24mm. This is low for me when amongst grandeur like Iceland offers. Even though I had lens coverage down to 18mm, I rarely used it, but found the 24-35mm length much more useful.
In my trip previous to that, the proportion of "keepers" at 35mm or less was about 37%, with just less than 20% at 24mm. And on that trip, the widest I had was 24mm.
Yes, there's a place for wider than 24mm, and some truly spectacular shots are possible, but you're also looking at diminishing returns.
The toughest part with shooting wide or ultra wide is finding a view that does not include other tourists and photographers who want to be everywhere, even during the less-touristy golden hours. They are everywhere, well off the marked trails, sitting on cliff edges, etc., even when it is clearly marked/signed to stay in the trails! Cloning/healing are useful tools!