Silence and noble silence are very different
These are all occurrences of noble silences in suttas
Mn26 and an9.4
Good, mendicants! It’s appropriate for gentlemen like you, who have gone forth in faith from the lay life to homelessness, to sit together and talk about the teaching. When you’re sitting together you should do one of two things: discuss the teachings or keep noble silence.
Note when thoughts came to moggalana’s mind buddha instructed moggalana to not neglect noble silence this means noble silence is mind silence Or a state free of thoughts and external silence, not just external silence
Sn21.1
Venerable Mahāmoggallāna said this:
“Just now, reverends, as I was in private retreat this thought came to mind: ‘They speak of this thing called “noble silence”. What then is this noble silence?’
It occurred to me: ‘As the placing of the mind and keeping it connected are stilled, a mendicant enters and remains in the second absorption, which has the rapture and bliss born of immersion, with internal clarity and confidence, and unified mind, without placing the mind and keeping it connected. This is called noble silence.’
And so, as the placing of the mind and keeping it connected were stilled, I was entering and remaining in the second absorption, which has the rapture and bliss born of immersion, with internal clarity and confidence, and unified mind, without placing the mind and keeping it connected.
While I was in that meditation, perceptions and attentions accompanied by placing the mind beset me.
Then the Buddha came up to me with his psychic power and said, ‘Moggallāna, Moggallāna! Don’t neglect noble silence, brahmin! Settle your mind in noble silence; unify your mind and bring it to immersion in noble silence.’
An8.2
When in the Saṅgha they don’t engage in motley talk or unworthy talk. Either they talk on Dhamma, or they invite someone else to do so, or they respect noble silence. This is the seventh cause.
Ud 2.2, ud3.8 and ud3.9
Mendicants, it is not appropriate for you gentlemen who have gone forth in faith from the lay life to homelessness to talk about such things. When you’re sitting together you should do one of two things: discuss the teachings or keep noble silence.”
Now for silence which is only external silence without mind silence
Dn3 and mn35
So the Buddha said to him, “Answer now, Ambaṭṭha. Now is not the time for silence. If someone fails to answer a legitimate question when asked three times by the Buddha, their head explodes into seven pieces there and then
Dn3
He said to the Buddha, “Would Master Gotama together with the mendicant Saṅgha please accept today’s meal from me?” The Buddha consented in silence.
Dn5
But the brahmin Kūṭadanta sat in silence. So those brahmins said to him, “How can you not applaud the ascetic Gotama’s fine words?”
It’s not that I don’t applaud what he said. If anyone didn’t applaud such fine words, their head would explode!
Dn18
That is the topic on which Brahmā Sanaṅkumāra spoke. And while he was speaking on that topic, each of the gods fancied, “The one sitting on my couch is the only one speaking.”
When one is speaking,
all the forms speak.
When one sits in silence,
they all remain silent.
But those gods imagine—
the Thirty-Three with their Lord—
that the one on their seat
is the only one to speak.
Mn86
Don’t take this road, ascetic. On this road there is a bandit named Aṅgulimāla. He is violent, bloody-handed, a hardened killer, merciless to living beings. He has laid waste to villages, towns, and countries. He is constantly murdering people, and he wears their fingers as a necklace. People travel along this road only after banding closely together in groups of ten, twenty, thirty, forty, or fifty. Still they meet their end by Aṅgulimāla’s hand.” But when they said this, the Buddha went on in silence.
For a second time … and a third time, they urged the Buddha to turn back.
But when they said this, the Buddha went on in silence.
Sn41.5
Well then, sir, please wait a moment while I consider the meaning of this.” Then after a short silence Citta said to Kāmabhū:
Now these are noble silence mistaken to be silence by people without physic power
Mn91
After eating he sits for a while in silence, but doesn’t wait too long to give the verses of appreciation. After eating he expresses appreciation without criticizing the meal or expecting another one. Invariably, he educates, encourages, fires up, and inspires that assembly with a Dhamma talk. Then he gets up from his seat and leaves.
Sn9.10
Now at that time that mendicant had previously been spending too much time in recitation. But some time later they adhered to passivity and silence.
Sn21.4
Is it really true, monk, that after your meal, on your return from alms-round, you entered your dwelling, where you adhered to passivity and silence, and you didn’t help the mendicants out when it was time to sew robes?”
An2.32
Then the bad mendicants continually adhere to silence in the midst of the Saṅgha, or they leave for some place or other. This is for the welfare and happiness of the people, for the benefit, welfare, and happiness of gods and humans.”
So noble silence includes silence for in noble silence there’s no external silence but silence is not noble silence for there’s no mind silence in silence
After all buddha is simple and he wouldn’t introduce unnecessary word if existing word can be used the fact that he introduced noble to silence mean that’s something that existing word like silence can’t do
What’s really important is noble silence can only be recognized by buddha,gods and arahant with physic power so sometimes you are in noble silence but people mistaken it to be silence