Does it take a ships captain to know a ship is unevenly loaded if the ship is listing. Does it take a mechanic to known if a car is overloaded it the chassis is 2 inches from the ground?
Bloat is anything you don't need, don't want, that takes up space and consumes resources. What I consider bloat, someone else would consider essential. If it's a feature you don't want, it's bloat.
What do you expect when a computer has a 20 core chip and 16GB of RAM? Apple's hardware is compensation for bloated software. Try running said software on dual core, 2GB machine.
A 500hp, 1200lbs-ft torque truck would have no problem towing a 2000lbs load. Try towing the same load with a 200hp, 300lbs-ft torque sedan.