I'm guessing here, so correct me if I'm wrong. Your impression may derive from the films.
PJ in the LoTR films totally ruined
Frodo compared to the book. Elijah Wood, whatever his merits as an actor may be (I hardly know anything he did besides LoTR, so I am very unqualified to judge), was only 18 when selected in 1999 for the role of Frodo. Who was 33 (coming of
Hobbit Age) at the Long-expected Party. Elijah did not look that age.
Then PJ cut out the 17 years between the L-eP and Frodo and
Sam (but without
Pippin!) left
Bag end, just after Frodo had turned 50.
Elijah Wood is only 39 today ...
PJ reduced his "Frodo" to a drug junkie far too early (he messed up Martin Freeman's
Bilbo in "The Hobbit" film series almost as badly).
The book Frodo was much wiser, both in the first meeting of Frodo and Sam with
Gollum in the
Emyn Muil, and very much more forcefully in "The Two
Towers", Book Two, chapter III "The
Black Gate is Closed". An eye-opener for Gollum, but for Sam, too:
"... You revealed yourself to me just now, foolishly.
Give it back to Sméagol you said. Do not say that again! Do not let that thought grow on you! You will never gat it back. But the desire of it may betray you to a bitter end. You will never get it back. In the last need, Sméagol, I should put on the
Precious; and the Precious mastered you long ago. If I, wearing it, were to command you, you would obey, even if it were to leap from a precipice or to cast yourself into the fire. And such would be my command. So have care, Sméagol!"
Bear with me.
Sauron interrogated Gollum, and put a fear in him that was certainly the most impressive possible in
Middle-earth.
But he let him go (and I can't help but mention my favorite obsession that Sauron detected something in Gollum indomitable even by himself - dang, those
Hobbits are
tough!)
Gandalf's "interview" with Gollum was probably close to "Geneva Convention" rules compared to Sauron's.
Frodo tells Gollum flat out "I will kill you by making you commit suicide", no ifs, ands or buts.
And perhaps consider that Gollum had no illusions about Sauron or even Gandalf. But that this very distant cousin of his, "just another Hobbit", would threaten him more directly with death than those "biggies" - to continue with my quote:
"Sam looked at his master with approval, but also with surprise: there was a look in his face and a tone in his voice that he had not known before. It had always been a notion of his that the kindness of dear Mr. Frodo was of such a high degree that it must imply a fair measure of blindness. Of course, he also held the incompatible belief that Mr. Frodo was the wisest person in the world (with the possible exception of Old Mr. Bilbo and Gandalf). Gollum in his own way, and with much more excuse as his acquaintance was much briefer, made have made a similar mistake, confusing kindness and blindness. At any rate this speech abashed and terrified him. He grovelled on the ground and could speak no clear words but
nice master."
The unexpected from a perceived marshmallow can be more terrifying than the expected from a terrifyingly powerful
Maia ...
or something like that. I'm thinking of the swordplay / martial arts tornado that Yoda unleashed on "
Saruman's" character in one of the Star
Wars prequel films. "Saruman" was reduced to throwing one dirty trick after another at Yoda to save his butt ...
"... rip
the ring from Frodo's neck …"
I see technical problems there. "Fellowship" Book Two, chapter I "Many Meetings", when Bilbo wants to see
the One Ring again:
"When he had dressed, Frodo found that while he slept the Ring had been hung about his neck on a new chain, light but strong."
What could this be?
Mithril.
That chain would
never break. If short enough, no pulling it over Frodo's head, a clasp needs to be opened. How could Gollum "know" this? If there is a mention anywhere before Frodo and Sam (and Gollum) enter
Mordor, I haven't found it.
But climbing Mount Doom:
"... Gollum was tearing at his master, trying to get at the chain and the Ring. This was probably the only thing that could have roused the dying embers of Frodo's heart and will: an attack, an attempt to wrest his treasure from him by force. He fought back with a sudden fury that amazed Sam, and Gollum also. … Frodo flung him off and rose up quivering."
Very little of this, in my imperfect memory, made it into PJ's film, too subtle for filmmaking perhaps (an excuse that PJ would gladly put forward, be it true or not). Gollum wasn't a slavish
Orc of Sauron's, he had conflicting issues about the One Ring. It was only after Frodo and Sam had escaped the
Tower of Cirith Ungol that Gollum apparently realized what Frodo was up to. That time, Sam drove him off, IIRC. Up to
Cirith Ungol, Gollum was helping Frodo as he was able, not knowing Frodo's true intentions. Up to then it was Frodo 'n' Sam
and Gollum, Afterwards it was Sam 'n' Frodo
against Gollum (and some tertiary character depicted as a strange searchlight atop a big tower, at least in PJ's version …

).