This is actually not really true. Competition bikes have a minimum weight nowadays, and technology is that advanced that it wouldn't be a problem to add some weight here or there because the bike would stay the same weight in total as they have so much margin else to keep in track with the minimum weight. This is why most teams have switched to disk brakes btw, and that they can have all the electronics onboard with power meter, bike computer etc.
But there's rolling "sprung" vs. static "unsprung" weight (the examples you listed). You care a lot more about rolling weight as that affects the acceleration characteristics of the wheel - that's really important at the limits.
If you bother to do the math, but simplify things so that all the mass of wheels is at the contact patch, you'll end up that rotating mass has twice the kinetic energy and takes 2x effort to accelerate and decelerate. Now if you check how large fraction of the mass of rider and bike the wheels are and how fast bikes accelerate, it's kind of insignificant.
Technology was advanced to routinely end up with bikes beneath the minimum, but those days are over. With wider tires, disc brakes, excessive focus on aerodynamics and even wider gear ranges they are usually racing considerably above the limit. These days you'll find bikes in the range of 5000 euros advertised that are considerably heavier than what you would have got for 1500 ten years ago.
