I've done bonkers hilly audaxes (vv slowly) with a triple - they would have been really miserable on my 1x.
I've also done the same lumpy 200k with triple and 1x - it was easier with a triple!
Worse on 1x because of ratio gaps, or something else ?
My 1x doesn't have a nice low ratio, so that's the problem. When I ride it on the flat, it does the job OK, but it's
much nicer having the closer ratios I have on my triple bikes.
I CAN ride with biggish gaps but it's much less enjoyable, especially on longer rides.
The gaps I would need with 10-11 speed to get the
range I currently I have would be - for me - a major pain. Of course I
could ride around with a Sturmey 3-speed, but it's not my choice for a dream bike!
1x has it's place - my commute is fine, and I use the same bike on shorter moderate hilly rides. And I race CX quite happily on 1 ring.
Both of these activities only need quite a narrow gear range.