There are also certain disadvantages or tradeoffs as you move up in price.
Carbon wheels are a bit lighter but MUCH noisier and offer a poor braking surface.
You can get disc brakes to offset the braking disadvantage, but they are heavier, negating the weight savings from the wheels.
Electronic shifting from what I understand is well liked by those who use it, but a bit heavier and requires recharging a battery every few days or perhaps once a week. A minor annoyance.
In addition, you'll be getting a lot of carbon components: bars, seatpost, saddle rails, etc. You'll have to be more careful with torque when installing or adjusting.
All of this is in the service of lighter weight for the most part, yet results in negligible, largely non existent performance gains.