Before World War I, you didn’t need a passport to travel internationally.
It was a self-evident truth that a sovereign individual could travel anywhere he wanted without asking for anyone’s permission.
Unfortunately, that’s not how travel works today.
Your so-called freedom of movement depends on getting multiple governments’ blessings.
You need to get a passport from your home government—possibly one that contains your immutable biometric information—and a visa from the government of your destination country and further visas from the governments of any country you transit to get there.
In addition to passports and visas, governments can impose ridiculous and invasive medical conditions to enter their territories, as the Covid mass psychosis proved.
Instead of an inalienable right, governments treat travel as a special privilege they grant the plebs that can be taken away if they misbehave—much like how an adult treats a child’s request to go to a friend’s house.
In reality, passports do not facilitate travel. They are tools for governments to control and coerce you. The world would be better off without them.
Unfortunately, passports are not going away.
You will continue to need a passport to travel, so you might as well have more than one to dilute your home government’s ability to control you.