When I first started riding with my bike "beefed up" with rack, lights, hub generator, wider tires etc. it was frustrating when I got into any hills. I was used to being a good climber and 10 pounds of additional bike and more when you add gear really changed the effort that it took to climb. I was straining on hills that I'd have danced up before.
Passage of time, swap for a compact crankset, and many more long distance miles under my belt and the bike is perfect for those long rides. It's comfortable and mentally I'm prepared for the adjusted riding speed. I hit the road on a recent 1000k with a bike and gear that weighed around 38 pounds.
When I get on my lightweight bike -- one that I built up because I was getting frustrated with my "hummer" as I call the rando bike -- it's a treat. I can do a nice all-daylight 200k Permanent in a lot less time. It's comfortable enough to spend 8-10 hours in the saddle yet less than half the weight. I enjoy both bikes.
It's all about mental attitude, expectation and comfort. Having said that, the 1000k ride where I was carrying my gear for three days, i.e. no drop bags, is as close to touring as I'll ever get (I think). I cannot imagine loading up with 100 pounds of gear in panniers and a bike-trailer and crossing the country !