I don't think you'd have much trouble touring with a reasonably light load on most of today's road bikes in the 13 - 15 pound range. But there would be some compromises as a result of how those bikes are set up and built compared to a touring bike that weighs 10 or so pounds more.

Light racing wheels can hold up to a lot of stress, but they aren't as tolerant of spoke failures as my touring wheels. When a spoke breaks on one of the light, minimal spoke-count wheels on one of our club rides it needs considerable tweaking to continue at all and frequently has resulted in a call for a ride to get back home. OTOH, I've broken a spoke on one of my 36 spoke touring wheels and was able to just keep riding for the rest of the day with the wheel being a bit out of true but still clearing the brake pads.

And most light carbon frames aren't designed for touring which frequently calls for wider tires, clearance for fenders, rack mounts, etc. I've found that a rack can still be attached without too much trouble, but it's not quite as convenient, and it's usually possible to make it through the occasional rough gravel road on 23mm tires - but it's easier and less stressful with 32mm ones.

So it's a question of what tradeoffs you want to make - with a reasonably light camping load (say 15 lbs. or so) and a 13 lb. bike you should be able to climb faster than on a heavier bike with only a few compromises. But it will be more costly and might make you a little more nervous on difficult terrain - so how much is the slightly faster speed worth to you?