The Root/Spiral of Origin is not intrinsically linked to magecraft at all.
There are many, many theoretically ways of reaching the Root. Hell, Ryougi Shiki was born out of the Root with a link to it, and she did not have to do anything or learn any magecraft.
The House of Tohsaka has been attempting to reach the Root with martial arts (likely via the state of absolute tranquility/zen or something along those lines).
KnK discussed that all of the World's mysticism and traditions can trace their origins back to the Root. Basically if you studied any discipline to the extreme, you can potentially hit the Root.
It is not that hard to comprehend that a Magic was a means to reach the Root.
Let's take Araya for example.
His thesis was that through the repetition of human lives in his distorted boundary field, he could explore the meaning of life/death and reach the Root.
Some aspects of the boundary field, e.g. the Moebius Space, already bordering on Magic.
If he actually succeeded, his boundary field magecraft would truly quality as a True Magic.
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Mahoyo is essentially a deep dive into Magic.
Most of the stuff you heard here about Magic came from like 3 info-dump scenes from Mahoyo.