Yep. A heavier bicycle is cheaper, less fragile, and also increases the workout effect. As long as a bicycle isn't 20 kg / 50 lbs, what is the real problem? I believe the real goal for lightness is luxury conspicuous consumption to maximize cost using exotic materials like beryllium.
If you push 300W on a 5kg bike or 20kg bike, the "workout effect" will be the same.
At the end of the day, if you are looking for "workout effect", it means that you're trying to achieve something, like winning races or going faster.
And for a given rider, with a certain weight and certain physiological abilities, they will go much faster on a 5kg bike than on a 20kg bike.
There is a whole world between <$1k bikes and those >$2k ones.
Weight being an important part.
Not only because it reduce the total weight of bike + rider, but also because a 5kg bike behave in a very different way than a 20kg.
It's like saying that cooking with a chef knife is the same as cooking with a sword.
Sure, after a certain point, the race for removing a few grams here or there is a luxury and many people tend to believe that spending $$$ on a lighter bike will fix their lack of fitness.
But modern bikes provide a completely difference than the old, heavy ones.
