I'll have to disagree with your explanation of the genesis of supermassive black holes. these monsters probably formed by the direct collapse of the huge amounts of gas present in the centers of these galaxies when they first formed. After they formed, there was still a lot of gas around, and quickly formed a massive accretion disk. These accretion disks along with super powerful jets spewing from the poles, formed quasars, the brightest objects in the universe.
would the gas first compressed enough to ignite into stars before taking on so much mass they collapse?
I think so. These massive blue-white stars would - I think - still need to go nova before becoming a BH.
Or would they?
Although the gas may eventually become compressed enough to start fusion, if there is enough gas falling in, the fusion will never produce sufficient energy to counter the crushing gravity. A relative state of equilibrium between gravity and the outward flow of energy will never be established. You really can't consider this a star. Gravity wins out and a black hole is created.
This is all made up... stars most likely form from an electrical pinch in a birkeland current; there may not be any fusion going on in stars; you can't believe everything you read on wikipedia
What you are describing is simply a hypergiant. They will start nuclear fusion, but collapse very quickly, within a few million years. But even such conditions are very, very rare. To directly form a black hole, the density would have to be greater than anything observed in the universe today. There may be a couple of such corner cases, but thus far, all supermassive black holes discovered were formed from stellar collapse and subsequent mergers.
However, moments after the big bang, this may have happened though - the density was trillions of times higher. Enough to create what are called primordial black holes.
Big bang? The big bang is mathematically impossible... also big bang universes cannot exist in black hole universes... black holes can't exist in black hole universes. The theory of star creation as coalescing from gravity is completely flawed... ha ha.. yes. bones quotes wikipedia... heaven help us.
https://steemit.com/science/@steemir/why-were-dinosaurs-so-big-the-truth-about-black-holes-and-other-physics-fairy-tales#@steemir/re-wizwom-re-steemir-why-were-dinosaurs-so-big-the-truth-about-black-holes-and-other-physics-fairy-tales-20160814t162352531z
https://steemit.com/science/@steemir/has-relativity-been-proven-black-holes-and-flying-dinosaurs-debunked-part-deux
No, I am describing a "quasi-star." https://en.wikipedia.org/wiki/Quasi-star Science actually doesn't know for sure what the progenitors of supermassive black holes were. There are several hypotheses at this time.
Quasi-stars and primordial black holes seem to be the same thing. You'll see the important point for both are "very early in the Universe's history".