Not sure why one would not get citizenship when they have GC.
But, assuming you are "clean," there are people to advocate for you so applying for citizenship should be a safe bet and would get you the guarantee of remaining in and traveling to and from the US for the rest of your life. If you intend to live here for the foreseeable future, I'd recommend giving it a go lest this administration decide to start trying to arbitrarily yank GCs.
If you are already a green card holder, you are already subject to the tax and other reporting requirements like a US citizen so the only real difference from the US perspective is you can't vote and aren't guaranteed to be able to cross the US border. It's that last bit that most people really want.
https://www.irs.gov/individuals/international-taxpayers/freq...
"if you are a U.S. citizen or a resident alien living outside the United States, your worldwide income is subject to U.S. income tax, regardless of where you live"
And also stripping the citizenship of all the babies that one doctor or nurse has delivered over their career because they have lied at least once on a form.
I firmly believe that the current administration would love to change the rules on citizenship. However the 14th amendment is extremely clear on this, and the courts have consistently ruled for decades that Congress and the President do not have the right to change the laws to strip citizenship from people. (This was extensively litigated over laws against dual citizenship.)
Therefore it is no more reasonable to fear the current administration making citizenship revocable than to fear the previous administration taking all the guns away.
The most recent decision relevant to this topic was https://en.wikipedia.org/wiki/Maslenjak_v._United_States in 2017. It was a 9-0 decision that a naturalized citizen who had made minor errors of fact in their citizenship declaration couldn't have their citizenship stripped because of that.
Between stare decisis and how solidly the court has been in protecting citizenship, this principle is not in any sort of trouble any time soon.
[1] https://www.vox.com/2018/8/30/17800410/trump-passport-birth-...
The law itself is solid. Whether a particular person with paperwork issues will be given the presumption of the facts being in their favor is another story.
The end result is people can and do lose their citizenship status pretty often. Debating whether it is strictly unlawful is really besides the point.