> Green card holders are essentially long term visas with citizenship grants for good behavior
No.
One of the major distinctions being – CBP cannot deny a green card holder to enter the country. They can try pressure tactics to 'convince' the person to 'voluntarily' give up their green card but, if they don't sign anything, they will still be let in. If there's something off about their case, they may be referred to an immigration judge, which is the only way to revoke a green card (barring some fraud detected by USCIS).
Contrast that with visas. They are entirely at immigration discretion and can be canceled at any time, including at the port of entry, for any reason. Visas which grant work authorization still have the SSN restricted and it's tied to whatever authorization the person has. A green card holder can remove the SSN restriction and their SSN is exactly the same as a citizen.
Really, the main differences are that a citizen can hold some offices a LPR cannot, the ability to vote, and no requirement to renew anything. And, most importantly, no residency requirements for a citizen.
As you point out, naturalization is more difficult to remove, but green cards aren't that easy either.
That is a pre-indicated stipulation of the green card validity, not revocation based on the whim of an evaluating (non-immigration judicial) official -- ie CBP and DHS and ICE cannot (read: should not be able to) revoke green cards.
The "basic US presence" requirement of green cards has always been present in the validity clause alongside the 5-10year expiry date, and not committing immigration fraud and other basic requirements to maintain green card -- a comical number of European green card holders gloss over/forget this clause every year, that is made explicit to them upon receiving the card and proceed to forfeit their green cards by not entering the US for over a year -- that is not a revocation (implies a subjective decision made by an official), it is a lapse of validity (implies some pre-stated condition was fulfilled).
Yes. People are generally familiar with rights that can lapse if eligibility is not maintained - consider the right to vote in state elections, which you lose if you fail to maintain residency in that state. Nobody yanked your state voter registration or your eligibility for in-state tuition, you abandoned it.
No.
One of the major distinctions being – CBP cannot deny a green card holder to enter the country. They can try pressure tactics to 'convince' the person to 'voluntarily' give up their green card but, if they don't sign anything, they will still be let in. If there's something off about their case, they may be referred to an immigration judge, which is the only way to revoke a green card (barring some fraud detected by USCIS).
Contrast that with visas. They are entirely at immigration discretion and can be canceled at any time, including at the port of entry, for any reason. Visas which grant work authorization still have the SSN restricted and it's tied to whatever authorization the person has. A green card holder can remove the SSN restriction and their SSN is exactly the same as a citizen.
Really, the main differences are that a citizen can hold some offices a LPR cannot, the ability to vote, and no requirement to renew anything. And, most importantly, no residency requirements for a citizen.
As you point out, naturalization is more difficult to remove, but green cards aren't that easy either.