That’s right.
It may help to think of jhana as a…tool, an exquisitely subtle instrument for dealing with delusion and ignorance, a scalpel for cutting attachment and craving.
And tools are discovered and re-discovered for many a purpose. As @hmong.buddhism points out, the Buddha did indeed attain the dimension of perception and non-perception. So this tool, this meditation, was used before, by Uddaka (not by Kalama, who taught the dimension of nothingness, which immediately precedes perception/non-perception). This meditation to the level of perception and non-perception was used before.
What then did the Buddha do differently? The Buddha was not happy with dimension of perception and non-perception.
Unsatisfied, the Buddha searched deeper:
MN26:18.1: And so, being myself liable to be reborn, understanding the drawbacks in being liable to be reborn, I sought the unborn supreme sanctuary, extinguishment—and I found it. Being myself liable to grow old, fall sick, die, sorrow, and become corrupted, understanding the drawbacks in these things, I sought the unaging, unailing, undying, sorrowless, uncorrupted supreme sanctuary, extinguishment—and I found it.
What did he find? Sariputta describes it this way:
DN34:1.2.11: What one thing should be given up?
DN34:1.2.12: The conceit ‘I am’.
Many can acquire a scalpel and cut with it. But a skilled surgeon understands how to apply the surgical instrument properly.
Meditation is like a scalpel. It cuts through the illusions of what we talk about as “reality”. Meditation cuts to the formless realms, allowing us to step back from the forms we habitually call “real”.
But the Buddha had the insight to use the scalpel of meditation in a different way than before. The Buddha used meditation to cut away the conceit, “I am”. With conceit cut away, he became an arahant. So this use of meditation, this use of meditation to cut away identity view, is a distinguishing factor of jhana.